PREPARATION OF PROPYLIMINE-FUNCTIONAL ORGANOSILICON COMPOUNDS AND PRIMARY AMINOPROPYL-FUNCTIONAL ORGANOSILICON COMPOUNDS

Abstract
An organosilicon compound with a primary aminopropyl-functional group is prepared. A catalyzed reductive amination process for combining a secondary propylimine-functional organosilicon compound with ammonia and hydrogen produces the primary aminopropyl-functional organosilicon compound.
Description
FIELD

A process for preparing a propylimine-functional organosilicon compound and a primary aminopropyl-functional organosilicon compound is disclosed. More particularly, the process includes protection of a propylaldehyde-functional organosilicon compound via formation of a propylimine group from the propylaldehyde group and subsequent reductive amination of the propylimine-functional organosilicon compound with ammonia.


INTRODUCTION

Certain amino-functional polyorganosiloxanes are useful, for example, in textile and leather treatment applications. Other amino-functional polyorganosiloxanes, such as amine-terminated polydiorganosiloxanes are useful in personal care applications, such as hair care. Amine-terminated polydiorganosiloxanes may be useful, for example, in hair conditioning applications. Amino-functional polyorganosiloxanes made by condensation may suffer from the drawback of instability as shown by viscosity changes and/or development of an ammonia odor after aging, which is undesirable for personal care applications. Traditionally, primary amino-functional polyorganosiloxanes are expensive to make by equilibration as they require costly starting materials and catalysts and require multiple process steps to complete.


Another method for making amino-functional polyorganosiloxanes uses allylamine, or a derivative that hydrolyzes into allylamine. These are used to do hydrosilylation chemistry with SiH functional polymers to form the amino-functional polyorganosiloxanes; however, this method suffers from the drawback that the amino-functional polyorganosiloxane product may contain at least trace amounts of either SiH or allylamine, either of which would have to be removed before the product can be used in any personal care applications due to toxicity of allylamine and reactivity of the SiH.


Another method of making amino-functional polyorganosiloxanes is by ammonolysis of chloropropyl terminated siloxanes. This costly, multi-step method may suffer from the drawback of leaving residual salt (i.e., ammonium chloride) in the amine-terminated polyorganosiloxane product that may require extensive washing to remove, which is cost ineffective and poorly sustainable. Also, any residual ammonium chloride may produce a foul smell, which is undesirable for personal care applications.


Therefore, there is an unmet need in the organosilicon industry the need for a synthetic method to prepare a broad range of amino-functional organosilicon compounds with relatively high purity, high selectivity, and/or low cost.


SUMMARY

A process for preparing a propylimine-functional organosilicon compound is disclosed. The propylimine-functional organosilicon compound can be used to prepare a primary aminopropyl-functional organosilicon compound comprises combining, under conditions to effect a propylimine generation reaction, starting materials comprising a propylaldehyde-functional organosilicon compound and a primary amine source, thereby forming a reaction product comprising a propylimine-functional organosilicon compound and water. The process further comprises forming the primary aminopropyl-functional organosilicon compound from the propylimine-functional organosilicon compound via reductive amination.







DETAILED DESCRIPTION

In the process introduced above and described in detail below, the propylaldehyde-functional organosilicon compound may be a propylaldehyde-functional organosilicon compound which is known and may be made by known methods, such as those described in U.S. Pat. No. 4,424,392 to Petty; U.S. Pat. No. 5,021,601 to Frances et al.; U.S. Pat. No. 5,739,246 to Graiver et al.; U.S. Pat. No. 7,696,294 to Asirvatham; U.S. Pat. No. 7,999,053 to Sutton et al.; European Patent Application Publication EP 0 392 948 A1 to Frances; PCT Patent Application Publication WO2006027074 to Kühnle et al; and PCT Patent Application Publication WO2022081444 to Fisk, et al.


Hydroformylation

Alternatively, the propylaldehyde-functional organosilicon compound may be prepared by a hydroformylation process as described in U.S. Provisional Patent Application Ser. No. 63/330,571 filed on 13 Apr. 2022 and hereby incorporated by reference. This hydroformylation process comprises: 1) combining, under conditions to catalyze hydroformylation reaction, starting materials comprising (A) a gas comprising hydrogen and carbon monoxide, (B) a vinyl-functional organosilicon compound, and (C) hydroformylation reaction catalyst such as a rhodium/bisphosphoramidite ligand complex catalyst or rhodium/tetraphosphoramidite ligand complex catalyst, thereby forming a hydroformylation reaction product comprising the propylaldehyde-functional organosilicon compound. The starting materials used in the hydroformylation process may optionally further comprise (D) a solvent.


(A) Syngas

Starting material (A), the gas used in the hydroformylation process, comprises carbon monoxide (CO) and hydrogen gas (H2). For example, the gas may be syngas. As used herein, “syngas” (from synthesis gas) refers to a gas mixture that contains varying amounts of CO and H2. Production methods are well known and include, for example: (1) steam reforming and partial oxidation of natural gas or liquid hydrocarbons, and (2) the gasification of coal and/or biomass. CO and H2 typically are the main components of syngas, but syngas may contain carbon dioxide and inert gases such as CH4, N2 and Ar. The molar ratio of H2 to CO (H2:CO molar ratio) varies greatly but may range from 1:100 to 100:1, alternatively 1:10 and 10:1. Syngas is commercially available and is often used as a fuel source or as an intermediate for the production of other chemicals. Alternatively, CO and H2 from other sources (i.e., other than syngas) may be used as starting material (A) herein. Alternatively, the H2:CO molar ratio in starting material (A) for use herein may be 3:1 to 1:3, alternatively 2:1 to 1:2, and alternatively 1:1.


(B) Vinyl-Functional Organosilicon Compound

The vinyl-functional organosilicon compound has, per molecule, at least one vinyl group covalently bonded to silicon. Alternatively, the vinyl-functional organosilicon compound may have, per molecule, more than one vinyl group covalently bonded to silicon. Starting material (B) may be one vinyl-functional organosilicon compound. Alternatively, starting material (B) may comprise two or more vinyl-functional organosilicon compounds that differ from one another. For example, the vinyl-functional organosilicon compound may comprise one or both of (B1) a silane and (B2) a polyorganosiloxane.


Starting material (B1), the vinyl-functional silane, may have formula (B1-1): RAxSiR4(4-x), where each RA is a vinyl group; each R4 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, an acyloxy group of 2 to 18 carbon atoms, and a hydrocarbonoxy-functional group of 1 to 18 carbon atoms; and subscript x is 1 to 4. Alternatively, subscript x may be 1 or 2, alternatively 2, and alternatively 1. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, an acetoxy group of 2 to 18 carbon atoms, and an alkoxy-functional group of 1 to 18 carbon atoms. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and a hydrocarbonoxy-functional group of 1 to 18 carbon atoms. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 12 carbon atoms and an aryl group of 6 to 12 carbon atoms. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 8 carbon atoms and an aryl group of 6 to 8 carbon atoms. Alternatively, each R4 in formula (B1-1) may be independently selected from the group consisting of an methyl and phenyl.


Suitable alkyl groups for R4 may be linear, branched, cyclic, or combinations of two or more thereof. The alkyl groups are exemplified by methyl, ethyl, propyl (including n-propyl and/or isopropyl), butyl (including n-butyl, tert-butyl, sec-butyl, and/or isobutyl); pentyl, hexyl, heptyl, octyl, decyl, dodecyl, undecyl, and octadecyl (and branched isomers having 5 to 18 carbon atoms), and the alkyl groups are further exemplified by cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Alternatively, the alkyl group for R4 may be selected from the group consisting of methyl, ethyl, propyl and butyl; alternatively methyl, ethyl, and propyl; alternatively methyl and ethyl. Alternatively, the alkyl group for R4 may be methyl.


Suitable aryl groups for R4 may be monocyclic or polycyclic and may have pendant hydrocarbyl groups. For example, the aryl groups for R4 include phenyl, tolyl, xylyl, and naphthyl and further include aralkyl groups such as benzyl, 1-phenylethyl and 2-phenylethyl. Alternatively, the aryl group for R4 may be monocyclic, such as phenyl, tolyl, or benzyl; alternatively the aryl group for R4 may be phenyl.


Suitable hydrocarbonoxy-functional groups for R4 may have the formula —OR5 or the formula —OR3—OR5, where each R3 is an independently selected divalent hydrocarbyl group of 1 to 18 carbon atoms, and each R5 is independently selected from the group consisting of the alkyl groups of 1-18 carbon atoms and the aryl groups of 6-18 carbon atoms, which are as described and exemplified above for R4. Examples of divalent hydrocarbyl groups for R3 include alkane-diyl groups of empirical formula —CrH2r-, where subscript r is 2 to 8. The alkane-diyl group may be a linear alkane-diyl, e.g., —CH2—CH2—, —CH2—CH2—CH2—, —CH2—CH2—CH2—CH2—, or —CH2—CH2—CH2—CH2—CH2—CH2—, or a branched alkane-diyl, e.g.,




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Alternatively, R3 may be an arylene group such as phenylene, or an alkylarylene group such as:




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Alternatively, R3 may be a linear alkane-diyl group such as ethylene. Alternatively, the hydrocarbonoxy-functional group may be an alkoxy-functional group such as methoxy, ethoxy, propoxy, or butoxy; alternatively methoxy or ethoxy, and alternatively methoxy.


Suitable acyloxy groups for R4 may have the formula




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where R5 is as described above. Examples of suitable acyloxy groups include acetoxy. Vinyl-functional acyloxysilanes and methods for their preparation are known in the art, for example, in U.S. Pat. No. 5,387,706 to Rasmussen, et al., and U.S. Pat. No. 5,902,892 to Larson, et al.


Suitable vinyl-functional silanes are exemplified by vinyl-functional trialkylsilanes such as vinyltrimethylsilane and vinyltriethylsilane; vinyl-functional trialkoxysilanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, and vinyltris(methoxyethoxy)silane; vinyl-functional dialkoxysilanes such as vinylphenyldiethoxysilane, vinylmethyldimethoxysilane, and vinylmethyldiethoxysilane; vinyl-functional monoalkoxysilanes such as trivinylmethoxysilane; vinyl-functional triacyloxysilanes such as vinyltriacetoxysilane, and vinyl-functional diacyloxysilanes such as vinylmethyldiacetoxysilane. All of these vinyl-functional silanes are commercially available from Gelest Inc. of Morrisville, Pennsylvania, USA. Furthermore, vinyl-functional silanes may be prepared by known methods, such as those disclosed in U.S. Pat. No. 4,898,961 to Baile, et al. and U.S. Pat. No. 5,756,796 to Davern, et al.


Alternatively, (B) the vinyl-functional organosilicon compound may comprise (B2) a vinyl-functional polyorganosiloxane. Said polyorganosiloxane may be cyclic, linear, branched, resinous, or a combination of two or more thereof. Said polyorganosiloxane may comprise unit formula (B2-1):




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where RA and R4 are as described above; each Z is independently selected from the group consisting of a hydrogen atom and R5 (where R5 is as described above), subscripts a, b, c, d, e, f, and g represent numbers of each unit in formula (B2-1) and have values such that subscript a≥0, subscript b≥0, subscript c≥0, subscript d≥0, subscript e≥0, subscript f≥0, and subscript g≥0; a quantity (a+b+c+d+e+f+g)≥2, and a quantity (b+d+f)≥1, and subscript h has a value such that 0≤h/(e+f+g)≤1.5. At the same time, the quantity (a+b+c+d+e+f+g) may be ≤10,000. Alternatively, when e=f=g=0, then h≥0. Alternatively, in formula (B-2-1), each R4 may be independently selected from the group consisting of a hydrogen atom, an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 12 carbon atoms and an aryl group of 6 to 12 carbon atoms. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 8 carbon atoms and an aryl group of 6 to 8 carbon atoms. Alternatively, each R4 may be independently selected from the group consisting of methyl and phenyl. Alternatively, each Z may be hydrogen or an alkyl group of 1 to 6 carbon atoms. Alternatively, each Z may be hydrogen.


Alternatively, (B2) the vinyl-functional polyorganosiloxane may comprise (B2-2) a linear polydiorganosiloxane having, per molecule, at least one vinyl group; alternatively at least two vinyl groups (e.g., when in formula (B2-1) above, subscripts e=f=g=0). For example, said polydiorganosiloxane may comprise unit formula (B2-3): (R43SiO1/2)a(RAR42SiO1/2)b(R42SiO2/2)c(RAR4SiO2/2)d, where RA and R4 are as described above, subscript a is 0, 1, or 2; subscript b is 0, 1, or 2, subscript c≥0, subscript d≥0, with the provisos that a quantity (b+d)≥1, a quantity (a+b)=2, and a quantity (a+b+c+d)≥2. Alternatively, in unit formula (B2-3) the quantity (a+b+c+d) may be at least 3, alternatively at least 4, and alternatively>50. At the same time in unit formula (B2-3), the quantity (a+b+c+d) may be less than or equal to 10,000; alternatively less than or equal to 4,000; alternatively less than or equal to 2,000; alternatively less than or equal to 1,000; alternatively less than or equal to 500; alternatively less than or equal to 250. Alternatively, in unit formula (B2-3) each R4 may be independently selected from the group consisting of alkyl and aryl; alternatively methyl and phenyl. Alternatively, each R4 in unit formula (B2-3) may be an alkyl group; alternatively each R4 may be methyl.


Alternatively, the polydiorganosiloxane of unit formula (B2-3) may be selected from the group consisting of: unit formula (B2-4): (R42RASiO1/2)2(R42SiO2/2)m(R4RASiO2/2)n, unit formula (B2-5): (R43SiO1/2)2(R42SiO2/2)o(R4RASiO2/2)p, or a combination of both (B2-4) and (B2-5).


In formulae (B2-4) and (B2-5), each R4 and RA are as described above. Subscript m may be 0 or a positive number. Alternatively, subscript m may be at least 2. Alternatively subscript m be 2 to 2,000. Subscript n may be 0 or a positive number. Alternatively, subscript n may be 0 to 2000. Subscript o may be 0 or a positive number. Alternatively, subscript o may be 0 to 2000. Subscript p is at least 2. Alternatively subscript p may be 2 to 2000.


Starting material (B2) may comprise a vinyl-functional polydiorganosiloxane such as i) bis-dimethylvinylsiloxy-terminated polydimethylsiloxane, ii) bis-dimethylvinylsiloxy-terminated poly(dimethylsiloxane/methylvinylsiloxane), iii) bis-dimethylvinylsiloxy-terminated polymethylvinylsiloxane, iv) bis-trimethylsiloxy-terminated poly(dimethylsiloxane/methylvinylsiloxane), v) bis-trimethylsiloxy-terminated polymethylvinylsiloxane, vi) bis-dimethylvinylsiloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane/methylvinylsiloxane), vii) bis-dimethylvinylsiloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane), viii) bis-dimethylvinylsiloxy-terminated poly(dimethylsiloxane/diphenylsiloxane), ix) bis-phenyl,methyl,vinyl-siloxy-terminated polydimethylsiloxane, and x) a combination of two or more of i) to ix).


Methods of preparing linear vinyl-functional polydiorganosiloxanes described above for starting material (B2), such as hydrolysis and condensation of the corresponding organohalosilanes and oligomers or equilibration of cyclic polydiorganosiloxanes, are known in the art, see for example U.S. Pat. Nos. 3,284,406; 4,772,515; 5,169,920; 5,317,072; and 6,956,087, which disclose preparing linear polydiorganosiloxanes with vinyl groups. Examples of linear polydiorganosiloxanes having vinyl groups are commercially available from, e.g., Gelest Inc. of Morrisville, Pennsylvania, USA under the tradenames DMS-V00, DMS-V03, DMS-V05, DMS-V21, DMS-V22, DMS-V25, DMS-V-31, DMS-V33, DMS-V34, DMS-V35, DMS-V41, DMS-V42, DMS-V43, DMS-V46, DMS-V51, DMS-V52.


Alternatively, (B2) the vinyl-functional polyorganosiloxane may be cyclic, e.g., when in unit formula (B2-1), subscripts a=b=c=e=f=g=h=0. The cyclic vinyl-functional polydiorganosiloxane may have unit formula (B2-7): (R4RASiO2/2)d, where RA and R4 are as described above, and subscript d may be 3 to 12, alternatively 3 to 6, and alternatively 4 to 5. Examples of cyclic vinyl-functional polydiorganosiloxanes include 2,4,6-trimethyl-2,4,6-trivinyl-cyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane, and 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexavinyl-cyclohexasiloxane. These cyclic vinyl-functional polydiorganosiloxanes are known in the art and are commercially available from, e.g., Sigma-Aldrich of St. Louis, Missouri, USA; Milliken of Spartanburg, South Carolina, USA; and other vendors.


Alternatively, the cyclic vinyl-functional polydiorganosiloxane may have unit formula (B2-8): (R42SiO2/2)c(R4RASiO2/2)d, where R4 and RA are as described above, subscript c is >0 to 6 and subscript d is 3 to 12. Alternatively, in formula (B2-8), c may be 3 to 6, and d may be 3 to 6.


Alternatively, (B2) the vinyl-functional polyorganosiloxane may be oligomeric, e.g., when in unit formula (B2-1) above the quantity (a+b+c+d+e+f+g)≤50, alternatively ≤40, alternatively ≤30, alternatively ≤25, alternatively ≤20, alternatively ≤10, alternatively ≤5, alternatively ≤4, alternatively ≤3. The oligomer may be cyclic, linear, branched, or a combination thereof. The cyclic oligomers are as described above as starting material (B2-6).


Examples of linear vinyl-functional polyorganosiloxane oligomers may have formula (B2-10):




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where R4 is as described above, each R2 is independently selected from the group consisting of R4 and RA, with the proviso that at least one R2, per molecule, is RA, and subscript z is 0 to 48. Alternatively, subscript z may be 0 to 4, alternatively 0 or 1; and alternatively 0. Alternatively, when z=0 in formula (B2-10), the vinyl-functional polyorganosiloxane oligomer may have formula (B2-10a)




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where RA is vinyl, and R4 is as described above. Examples of linear vinyl-functional polyorganosiloxane oligomers may have include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane; 1,1,1,3,3-pentamethyl-3-vinyl-disiloxane; 1,1,1,3,5,5,5-heptamethyl-3-vinyl-trisiloxane, all of which are commercially available, e.g., from Gelest, Inc. of Morrisville, Pennsylvania, USA or Sigma-Aldrich of St. Louis, Missouri, USA.


Alternatively, the vinyl-functional polyorganosiloxane oligomer may be branched. The branched oligomer may have general formula (B2-11): RASiR123, where RA is vinyl as described above, and each R12 is selected from R13 and —OSi(R14)3; where each R13 is a monovalent hydrocarbon group (e.g., which may be an alkyl group of 1 to 18 carbon atoms or an aryl group of 6 to 18 carbon atoms, as described an exemplified above for R4); where each R14 is selected from R13, —OSi(R15)3, and —[OSiR132]iiOSiR133; where each R15 is selected from R13, —OSi(R16)3, and —[OSiR132]iiOSiR133; where each R16 is selected from R13 and —[OSiR132]iiOSiR133; and where subscript ii has a value such that 0≤ii≤100. At least two of R12 may be —OSi(R14)3. Alternatively, all three of R12 may be —OSi(R14)3.


Alternatively, in formula (B2-11) when each R12 is R13, the branched polyorganosiloxane oligomer has the following structure (B2-11a):




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where RA and R13 are as described above. Alternatively, in formula (B2-11a), each R13 may be methyl.


Alternatively, in formula (B2-11) when each R12 is —OSi(R14)3, each R14 may be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (B2-11b):




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where RA and R15 are as described above. Alternatively, each R15 may be an R13, as described above, and each R13 may be methyl.


Alternatively, in formula (B2-11), when each R12 is —OSi(R14)3, one R14 may be R13 in each —OSi(R14)3 such that each R12 is —OSiR13(R14)2. Alternatively, two R14 in —OSiR13(R14)2 may each be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (B2-11c):




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where RA, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R13 may be methyl.


Alternatively, in formula (B2-11), one R12 may be R13, and two of R12 may be —OSi(R14)3. When two of R12 are —OSi(R14)3, and one R14 is R13 in each —OSi(R14)3 then two of R12 are —OSiR13(R14)2. Alternatively, each R14 in —OSiR13(R14)2 may be —OSi(R15)3 such that the branched polyorganosiloxane oligomer has the following structure (B2-11d):




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where RA, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R13 may be methyl. Alternatively, the vinyl-functional branched polyorganosiloxane may have 3 to 16 silicon atoms per molecule, alternatively 4 to 16 silicon atoms per molecule, and alternatively 4 to 10 silicon atoms per molecule. Examples of vinyl-functional branched polyorganosiloxane oligomers include vinyl-tris(trimethyl)siloxy)silane, which has formula:




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methyl-vinyl-di((1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)oxy)-silane, which has formula




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and vinyl-tris((1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)oxy)-silane, which has formula




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Branched vinyl-functional polyorganosiloxane oligomers described above may be prepared by known methods, such as those disclosed in “Testing the Functional Tolerance of the Piers-Rubinsztajn Reaction: A new Strategy for Functional Silicones” by Grande, et al. Supplementary Material (ESI) for Chemical Communications, © The Royal Society of Chemistry 2010.


Alternatively, (B2) the vinyl-functional polyorganosiloxane may be branched, such as the branched oligomer described above and/or a branched vinyl-functional polyorganosiloxane that may have, e.g., more vinyl groups per molecule and/or more polymer units than the branched oligomer described above (e.g., in formula (B2-1) when the quantity (a+b+c+d+e+f+g)>50). The branched vinyl-functional polyorganosiloxane may have (in formula (B2-1)) a quantity (e+f+g) sufficient to provide >0 to 5 mol % of trifunctional and/or quadrifunctional units to the branched vinyl-functional polyorganosiloxane.


For example, the branched vinyl-functional polyorganosiloxane may comprise a Q branched polyorganosiloxane of unit formula (B2-13): (R43SiO1/2)q(R42RASiO1/2)r(R42SiO2/2)s(SiO4/2)t, where R4 and RA are as described above, and subscripts q, r, s, and t have average values such that 2≥q≥0, 4≥r≥0, 995≥s≥4, t=1, (q+r)=4, and (q+r+s+t) has a value sufficient to impart a viscosity >170 mPa·s measured by rotational viscometry (as described below with the test methods) to the branched polyorganosiloxane. Alternatively, viscosity may be >170 mPa·s to 1000 mPa·s, alternatively >170 to 500 mPa·s, alternatively 180 mPa·s to 450 mPa·s, and alternatively 190 mPa·s to 420 mPa·s. Suitable Q branched polyorganosiloxanes for starting material (B2-12) are known in the art and can be made by known methods, exemplified by those disclosed in U.S. Pat. No. 6,806,339 to Cray, et al. and U.S. Patent Publication 2007/0289495 to Cray, et al.


Alternatively, the branched vinyl-functional polyorganosiloxane may comprise formula (B2-14): [RARA2Si—(O—SiR42)x—O](4-w)—Si—[O—(R42SiO)vSiR43]w, where RA and R4 are as described above; and subscripts v, w, and x have values such that 200≥v≥1, 2≥w≥0, and 200≥x≥1. Alternatively, in this formula (B2-14), each R4 is independently selected from the group consisting of methyl and phenyl. Branched polyorganosiloxane suitable for starting material (B2-14) may be prepared by known methods such as heating a mixture comprising a polyorganosilicate resin, and a cyclic polydiorganosiloxane or a linear polydiorganosiloxane, in the presence of a catalyst, such as an acid or phosphazene base, and thereafter neutralizing the catalyst.


Alternatively, the branched vinyl-functional polyorganosiloxane for starting material (B2-11) may comprise a T branched polyorganosiloxane (silsesquioxane) of unit formula (B2-15): (R43SiO1/2)aa(RAR42SiO1/2)bb(R42SiO2/2)cc(RAR4SiO2/2)ee(R4SiO3/2)dd, where R4 and RA are as described above, subscript aa≥0, subscript bb≥0, subscript cc is 15 to 995, subscript dd>0, and subscript ee≥0. Subscript aa may be 0 to 10. Alternatively, subscript aa may have a value such that: 12≥aa≥0; alternatively 10≥aa≥0; alternatively 7≥aa≥0; alternatively 5≥aa≥0; and alternatively 3≥aa≥0. Alternatively, subscript bb≥1. Alternatively, subscript bb≥3. Alternatively, subscript bb may have a value such that: 12≥bb>0; alternatively 12≥bb≥3; alternatively 10≥bb>0: alternatively 7≥bb>1; alternatively 5≥bb≥2; and alternatively 7≥bb≥3. Alternatively, subscript cc may have a value such that: 800≥cc≥15; and alternatively 400≥cc≥15. Alternatively, subscript ee may have a value such that: 800≥ee≥0; 800≥ee≥15; and alternatively 400≥ee≥15. Alternatively, subscript ee may b 0. Alternatively, a quantity (cc+ee) may have a value such that 995≥(cc+ee)≥15. Alternatively, subscript dd≥1. Alternatively, subscript dd may be 1 to 10. Alternatively, subscript dd may have a value such that: 10≥dd>0; alternatively 5≥dd>0; and alternatively dd=1. Alternatively, subscript dd may be 1 to 10, alternatively subscript dd may be 1 or 2. Alternatively, when subscript dd=1, then subscript bb may be 3 and subscript cc may be 0. The values for subscript bb may be sufficient to provide the silsesquioxane of unit formula (B2-15) with a vinyl content of 0.1% to 1%, alternatively 0.2% to 0.6%, based on the weight of the silsesquioxane. Suitable T branched polyorganosiloxanes (silsesquioxanes) for starting material (B2-15) are exemplified by those disclosed in U.S. Pat. No. 4,374,967 to Brown, et al; U.S. Pat. No. 6,001,943 to Enami, et al.; U.S. Pat. No. 8,546,508 to Nabeta, et al.; and U.S. Pat. No. 10,155,852 to Enami.


Alternatively, (B2) the vinyl-functional polyorganosiloxane may comprise a vinyl-functional polyorganosilicate resin, which comprises monofunctional units (“M” units) of formula RM3SiO1/2 and tetrafunctional silicate units (“Q” units) of formula SiO4/2, where each RM is an independently selected monovalent hydrocarbon group; each RM may be independently selected from the group consisting of R4 and RA as described above. Alternatively, each RM may be selected from the group consisting of alkyl, vinyl, and aryl. Alternatively, each RM may be selected from methyl, vinyl, and phenyl. Alternatively, at least one-third, alternatively at least two thirds of the RM groups are methyl groups. Alternatively, the M units may be exemplified by (Me3SiO1/2), (Me2PhSiO1/2), and (Me2ViSiO1/2). The polyorganosilicate resin is soluble in solvents such as those described herein as starting material (D), exemplified by liquid hydrocarbons, such as benzene, ethylbenzene, toluene, xylene, and heptane, or in liquid non-functional organosilicon compounds such as low viscosity linear and cyclic polydiorganosiloxanes.


When prepared, the polyorganosilicate resin comprises the M and Q units described above, and the polyorganosiloxane further comprises units with silicon bonded hydroxyl groups, and/or hydrolyzable groups, described by moiety (ZO1/2), above, and may comprise neopentamer of formula Si(OSiRM3)4, where RM is as described above, e.g., the neopentamer may be tetrakis(trimethylsiloxy)silane. 29Si NMR and 13C NMR spectroscopies may be used to measure hydroxyl and alkoxy content and molar ratio of M and Q units, where said ratio is expressed as {M(resin)}/{Q(resin)}, excluding M and Q units from the neopentamer. M/Q ratio represents the molar ratio of the total number of triorganosiloxy groups (M units) of the resinous portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. M/Q ratio may be 0.5/1 to 1.5/1, alternatively 0.6/1 to 0.9/1.


The Mn of the polyorganosilicate resin depends on various factors including the types of hydrocarbon groups represented by RM that are present. The Mn of the polyorganosilicate resin refers to the number average molecular weight measured using GPC, when the peak representing the neopentamer is excluded from the measurement. The Mn of the polyorganosilicate resin may be 1,500 Da to 30,000 Da; alternatively 1,500 Da to 15,000 Da; alternatively>3,000 Da to 8,000 Da. Alternatively, Mn of the polyorganosilicate resin may be 3,500 Da to 8,000 Da.


U.S. Pat. No. 8,580,073 at col. 3, line 5 to col. 4, line 31, and U.S. Patent Publication 2016/0376482 at paragraphs [0023] to [0026] are hereby incorporated by reference for disclosing MQ resins, which are suitable polyorganosilicate resins for use as starting material (B2). The polyorganosilicate resin can be prepared by any suitable method, such as cohydrolysis of the corresponding silanes or by silica hydrosol capping methods. The polyorganosilicate resin may be prepared by silica hydrosol capping processes such as those disclosed in U.S. Pat. No. 2,676,182 to Daudt, et al.; U.S. Pat. No. 4,611,042 to Rivers-Farrell et al.; and U.S. Pat. No. 4,774,310 to Butler, et al. The method of Daudt, et al. described above involves reacting a silica hydrosol under acidic conditions with a hydrolyzable triorganosilane such as trimethylchlorosilane, a siloxane such as hexamethyldisiloxane, or mixtures thereof, and recovering a copolymer having M units and Q units. The resulting copolymers generally contain from 2 to 5 percent by weight of hydroxyl groups.


The intermediates used to prepare the polyorganosilicate resin may be triorganosilanes and silanes with four hydrolyzable substituents or alkali metal silicates. The triorganosilanes may have formula RM3SiX, where RM is as described above and X represents a hydroxyl group or a hydrolyzable substituent, e.g., of formula OZ described above. Silanes with four hydrolyzable substituents may have formula SiX′4, where each X′ is independently selected from the group consisting of halogen, alkoxy, and hydroxyl. Suitable alkali metal silicates include sodium silicate.


The polyorganosilicate resin prepared as described above typically contain silicon bonded hydroxyl groups, e.g., of formula, HOSiO3/2. The polyorganosilicate resin may comprise up to 3.5% of silicon bonded hydroxyl groups, as measured by FTIR spectroscopy and/or NMR spectroscopy, as described above. For certain applications, it may desirable for the amount of silicon bonded hydroxyl groups to be below 0.7%, alternatively below 0.3%, alternatively less than 1%, and alternatively 0.3% to 0.8%. Silicon bonded hydroxyl groups formed during preparation of the polyorganosilicate resin can be converted to trihydrocarbon siloxane groups or to a different hydrolyzable group by reacting the silicone resin with a silane, disiloxane, or disilazane containing the appropriate terminal group. Silanes containing hydrolyzable groups may be added in molar excess of the quantity required to react with the silicon bonded hydroxyl groups on the polyorganosilicate resin.


Alternatively, the polyorganosilicate resin may further comprise 2% or less, alternatively 0.7% or less, and alternatively 0.3% or less, and alternatively 0.3% to 0.8% of units containing hydroxyl groups, e.g., those represented by formula XSiO3/2 where RM is as described above, and X represents a hydrolyzable substituent, e.g., OH. The concentration of silanol groups (where X═OH) present in the polyorganosilicate resin may be determined using FTIR spectroscopy and/or NMR as described above.


For use herein, the polyorganosilicate resin further comprises one or more vinyl groups per molecule. The polyorganosilicate resin having vinyl groups may be prepared by reacting the product of Daudt, et al. with a vinyl group-containing endblocking agent and an endblocking agent free of aliphatic unsaturation, in an amount sufficient to provide from 3 to 30 mole percent of vinyl groups in the final product. Examples of endblocking agents include, but are not limited to, silazanes, siloxanes, and silanes. Suitable endblocking agents are known in the art and exemplified in U.S. Pat. No. 4,584,355 to Blizzard, et al.; U.S. Pat. No. 4,591,622 to Blizzard, et al.; and U.S. Pat. No. 4,585,836 to Homan, et al. A single endblocking agent or a mixture of such agents may be used to prepare such resin.


Alternatively, the polyorganosilicate resin may comprise unit formula (B2-17): (R43SiO1/2)mm(R42RASiO1/2)nn(SiO4/2)oo(ZO1/2)h, where Z, R4, and RA, and subscript h are as described above and subscripts mm, nn and oo have average values such that mm≥0, nn>0, oo>0, and 0.5≤(mm+nn)/oo≤4. Alternatively, 0.6≤(mm+nn)/oo≤4; alternatively 0.7≤(mm+nn)/oo≤4, and alternatively 0.8≤(mm+nn)/oo≤4.


Alternatively, (B2) the vinyl-functional polyorganosiloxane may comprise (B2-18) a vinyl-functional silsesquioxane resin, i.e., a resin containing trifunctional (T) units of unit formula: (R44SiO1/2)a(R42RASiO1/2)b(R42SiO2/2)c(R4RASiO3/2)d(R4SiO3/2)e(RASiO3/2)f(ZO1/2)h; where R4 and RA are as described above, subscript f>1, 2<(e+f)<10,000; 0<(a+b)/(e+f)<3; 0<(c+d)/(e+f)<3; and 0<h/(e+f)<1.5. Alternatively, the vinyl-functional silsesquioxane resin may comprise unit formula (B2-19): (R4SiO3/2)e(RASiO3/2)f(ZO1/2)h, where R4, RA, Z, and subscripts h, e and f are as described above. Alternatively, the vinyl-functional silsesquioxane resin may further comprise difunctional (D) units of formulae (R42Sio2/2)c(R4RASiO2/2)d in addition to the T units described above, i.e., a DT resin, where subscripts c and d are as described above. Alternatively, the vinyl-functional silsesquioxane resin may further comprise monofunctional (M) units of formulae (R43SiO1/2)a(R42RASiO1/2)b, i.e., an MDT resin, where subscripts a and b are as described above for unit formula (B2-1).


Vinyl-functional silsesquioxane resins are commercially available, for example. RMS-310, which comprises unit formula (B2-20): (Me2ViSiO1/2)25(PhSiO3/2)75 dissolved in toluene, is commercially available from DSC. Vinyl-functional silsesquioxane resins may be produced by the hydrolysis and condensation or a mixture of trialkoxy silanes using the methods as set forth in “Chemistry and Technology of Silicone” by Noll, Academic Press, 1968, chapter 5, p 190-245. Alternatively, vinyl-functional silsesquioxane resins may be produced by the hydrolysis and condensation of a trichlorosilane using the methods as set forth in U.S. Pat. No. 6,281,285 to Becker, et al. and U.S. Pat. No. 5,010,159 to Bank, et al. Vinyl-functional silsesquioxane resins comprising D units may be prepared by known methods, such as those disclosed in U.S. Patent Application 2020/0140619 and PCT Publication WO2018/204068 to Swier, et al.


Alternatively, starting material (B) the vinyl-functional organosilicon compound may comprise (B3) a vinyl-functional silazane. The vinyl-functional silazane may have formula (B3-1): [(R1(3-gg)RAggSi)ffNH(3-ff)]hh, where RA is as described above; each R1 is independently selected from the group consisting of an alkyl group and an aryl group; each subscript ff is independently 1 or 2; and subscript gg is independently 0, 1, or 2; where 1<hh<10. For R1, the alkyl group and the aryl group may be the alkyl group and the aryl group as described above for R4. Alternatively, subscript hh may have a value such that 1<hh<6. Examples of vinyl-functional silazanes include, MePhViSiNH2, Me2ViSiNH2, (ViMe2Si)2NH, (MePhViSi)2NH. Vinyl-functional silazanes may be prepared by known methods, for example, reacting a vinyl-functional halosilane with ammonia under anhydrous or substantially anhydrous conditions, and thereafter distilling the resulting reaction mixture to separate cyclic vinyl-functional silazanes and linear vinyl-functional silazanes, such as those disclosed in U.S. Pat. No. 2,462,635 to Haber; U.S. Pat. No. 3,243,404 to Martellock; and PCT Publication No. WO83/02948 to Dziark. Suitable vinyl-functional silazanes are commercially available, for example, 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane (MeViSiNH)3 is available from Sigma-Aldrich of St. Louis, MO, USA; sym-tetramethyldivinyldisilazane (ViMe2Si)2NH is available from Alfa Aesar; and 1,3-divinyl-1,3-diphenyl-1,3-dimethyldisilazane (MePhViSi)2NH is available from Gelest, Inc. of Morrisville, Pennsylvania, USA.


Starting material (B) may be any one of the vinyl-functional organosilicon compounds described above. Alternatively, starting material (B) may comprise a mixture of two or more of the vinyl-functional organosilicon compounds.


(C) Hydroformylation Reaction Catalyst

Starting material (C), the hydroformylation reaction catalyst for use herein comprises an activated complex of rhodium and a ligand. The ligand may be symmetric or asymmetric. Alternatively, the ligand may be symmetric. The ligand may comprise, alternatively may be, a bisphosphoramidite ligand. Alternatively, the ligand may comprise, alternatively may be, a tetraphosphoramidite ligand. Alternatively, the ligand may comprise, alternatively may be, a phosphine amine ligand. Alternatively, the ligand may comprise, alternatively may be, a phosphine ligand. Alternatively, starting material (C), the hydroformylation catalyst, may comprise a combination of rhodium/ligand complexes including different species of ligands.


The ligand has formula (C1), (C2), and/or (C3):




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where: R101-R122 are each independently selected from hydrogen, a hydrocarbyl group, a heteroaryl group, a halogen atom, or a heterocarbyl group, wherein two or more of R101-R122 may optionally be bonded together to give one or more cyclic moieties; each of X1-X4 is independently selected from O, CH2, NH, NR, NSO2R or NSO2A, where each R is an independently selected substituted or unsubstituted alkyl or aryl group and each A is an independently selected aryl or heteroaryl group; and each of Y1-Y8 is an independently selected nitrogen-containing heterocyclic moiety bonded to P via N, wherein each heterocyclic moiety may be substituted with one or more groups or atoms selected from alkyl, aryl, heteroaryl, alkoxy, acyl, carboxyl, carboxylate, cyano, —SO3H, sulfonate, amino, trifluoromethyl, and halogen.


The ligand may have formula (C1). Alternatively, the ligand may have formula (C2). Alternatively, the ligand may have formula (C3).


Suitable hydrocarbyl groups for R101-R122 may independently be linear, branched, cyclic, or combinations thereof. Cyclic hydrocarbyl groups encompass aryl groups as well as saturated or non-conjugated cyclic groups. Cyclic hydrocarbyl groups may be monocyclic or polycyclic. Linear and branched hydrocarbyl groups may independently be saturated or unsaturated. One example of a combination of a linear and cyclic hydrocarbyl group is an aralkyl group. By “substituted,” it is meant that one or more hydrogen atoms may be replaced with atoms other than hydrogen (e.g. a halogen atom, such as chlorine, fluorine, or bromine). Suitable alkyl groups are exemplified by, but not limited to, methyl, ethyl, propyl (e.g., iso-propyl and/or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and/or sec-butyl), pentyl (e.g., isopentyl, neopentyl, and/or tert-pentyl), hexyl, as well as branched saturated hydrocarbon groups of 6 carbon atoms. Suitable aryl groups are exemplified by, but not limited to, phenyl, tolyl, xylyl, naphthyl, benzyl, and dimethyl phenyl. Suitable alkenyl groups include vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, pentenyl, heptenyl, hexenyl, and cyclohexenyl groups. Suitable monovalent halogenated hydrocarbon groups include, but are not limited to, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms. Suitable halogenated alkyl groups are exemplified by, but not limited to, the alkyl groups described above where one or more hydrogen atoms is replaced with a halogen atom, such as F or Cl. For example, fluoromethyl, 2-fluoropropyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 4,4,4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, and 8,8,8,7,7-pentafluorooctyl, 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4-difluoro-5-methylcycloheptyl, chloromethyl, chloropropyl, 2-dichlorocyclopropyl, and 2,3-dichlorocyclopentyl are examples of suitable halogenated alkyl groups. Suitable halogenated aryl groups are exemplified by, but not limited to, the aryl groups described above where one or more hydrogen atoms is replaced with a halogen atom, such as F or Cl. For example, chlorobenzyl and fluorobenzyl are suitable halogenated aryl groups. Suitable heterocarbyl groups include any of the hydrocarbyl groups described above, but including one or more heteroatoms, such as oxygen, sulfur, or nitrogen. Suitable halogen atoms include F, Cl, Br, I, At, and Ts, alternatively F, Cl, and Br, alternatively Cl.


As described above, two or more of R101-R122 may optionally be bonded together to give one or more cyclic moieties. The cyclic moieties formed by a combination of any of R101-R122 may be aliphatic or aromatic, and may be monocyclic, bicyclic, or polycyclic.


By way of example, when the ligand has formula (C1), when R101, R102, R107, and R108 are each H, when R103 and R104 form an aliphatic cyclic ring, and R105 and R106 together form an aliphatic cyclic ring, the ligand of formula (C1) becomes the following formula (C1-1):




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where X1, X2, and Y1-Y4 are defined above.


As another example, when the ligand has formula (C1), when R101 R102, R107, and R108 are each H, and R103 and R104 form an aromatic ring, and R105 and R106 together form an aromatic cyclic ring, the ligand of formula (C1) becomes the following formula (C1-2):




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where X1, X2, and Y1-Y4 are defined above.


As yet another example, when the ligand has formula (C1), when R103, R104, R105, and R106 are each H, and R101 and R102 form a bicyclic aromatic structure, and R107 and R108 together form a bicyclic aromatic structure, the ligand of formula (C1) becomes the following formula (C1-3)




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where X1, X2, and Y1-Y4 are defined above.


Each of X1-X4 is independently selected from O, CH2, NH, NR, NSO2R or NSO2A, where each R is an independently selected substituted or unsubstituted alkyl or aryl group and each A is an independently selected aryl or heteroaryl group. Alternatively, each of X1-X4 may be O.


Each of Y1-Y8 is an independently selected nitrogen-containing heterocyclic moiety bonded to P via N, wherein each heterocyclic moiety may be substituted with one or more groups or atoms selected from alkyl, aryl, heteroaryl, alkoxy, acyl, carboxyl, carboxylate, cyano, —SO3H, sulfonate, amino, trifluoromethyl, and halogen. Each of Y1-Y8 may independently be monocyclic, bicyclic, and/or polycyclic. Exemplary examples of nitrogen-containing heterocyclic groups include indole groups, isoindole groups, pyrrole groups, carbazole groups, and imidazole groups. As noted above, any of the carbon atoms in these groups can be substituted with one or more groups or atoms selected from alkyl, aryl, heteroaryl, alkoxy, acyl, carboxyl, carboxylate, cyano, —SO3H, sulfonate, amino, trifluoromethyl, and halogen. Alternatively, at least one of Y1-Y8 may be substituted with an alkoxy group having from 1 to 8 carbon atoms. Alternatively, at least one of Y1-Y8 is substituted with an alkyl group having from 1 to 12 carbon atom, e.g. tert-butyl groups.


Alternatively, the ligand may have formula (C1), where R101-R108, X1-X2, and Y1-Y4 are selected such that the ligand is a bisphosphoramidite ligand having one of the following formulas (where Me indicates methyl and tBu indicates t-butyl):




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2,2′-bis((di(1H-indol-1-yl)phosphaneyl)oxy)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene



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2,2′-bis((bis(6-(4-methoxyphenyl)-1H-indol-1-yl)phosphaneyl)oxy)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene



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2,2′-bis((bis(6-(4-methoxyphenyl)-1H-indol-1-yl)phosphaneyl)oxy)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene



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2,2′-bis((bis(6-(3,5-di-tert-butylphenyl)-1H-indol-1-yl)phosphaneyl)oxy)-11′-binaphthalene



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1,1′,1″,1′″-(((4,4′,5,5′,6,6′-hexamethyl-[1,1′-biphenyl]-2,2′-diyl)bis(oxy))bis(phosphanetriyl))tetrakis(6-(3,5-di-tert-butylphenyl)-1H-indole), and



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2,2′-bis((bis(6-(3,5-di-tert-butyl-4-methoxyphenyl)-1H-indol-1-yl)phosphaneyl)oxy)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene

Methods of preparing the first ligand structure above in this section for formula (C1) are disclosed in U.S. Pat. No. 9,795,952 to Diebolt et al, which is incorporated by reference herein in its entirety.


Alternatively, the ligand may have formula (C2), and R109-R122, X1-X2, and Y5—Y8 are selected such that the ligand is a bisphosphoramidite ligand having one of the following formulas:




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7,7′-bis((bis(6-(3,5-di-tert-butylphenyl)-1H-indol-1-yl)phosphaneyl)oxy)-2,2′,3,3′-tetrahydro-1,1′-spirobi[indene] and



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7,7′-bis((di(1H-indol-1-yl)phosphaneyl)oxy)-2,2′,3,3′-tetrahydro-1,1′-spirobi[indene]

Alternatively, the ligand may have formula (C3), and R101-R106, X1-X4, and Y1-Y8 may be selected such that the ligand is a tetraphosphoramidite ligand having one of the following formulas:




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Methods of preparing these ligand structures above in this section for formula (C3) are disclosed in U.S. Pat. No. 7,531,698 to Zhang et al, which is incorporated by reference herein in its entirety.


Starting material (C), the rhodium/ligand complex catalyst, may be prepared by methods known in the art, such as those disclosed in U.S. Pat. No. 4,769,498 to Billig, et al. at col. 20, line 50-col. 21, line 40 and U.S. Pat. No. 10,023,516 to Brammer et al. col. 11, line 35-col. 12, line 12 by varying appropriate starting materials. For example, the rhodium/ligand complex catalyst may be prepared by a process comprising combining a rhodium precursor and the ligand described above under conditions to form the complex, which complex may then be introduced into a hydroformylation reaction medium comprising one or both of starting materials (A) and/or (B), described above. Alternatively, the rhodium/ligand complex catalyst may be formed in situ by introducing the rhodium catalyst precursor into the reaction medium, and the ligand into the reaction medium (e.g., before, during, and/or after introduction of the rhodium catalyst precursor), for the in situ formation of the rhodium/ligand complex catalyst. The rhodium/ligand complex catalyst can be activated by heating and/or exposure to starting material (A) to form the (C) rhodium/ligand complex catalyst. Rhodium catalyst precursors are exemplified by rhodium dicarbonyl acetylacetonate, Rh2O3, Rh4(CO)12, Rh6(CO)16, and Rh(NO3)3. Additional methods to prepare certain ligands are described herein in the appended Examples.


For example, a rhodium precursor, such as rhodium dicarbonyl acetylacetonate, optionally starting material (D), a solvent, and the ligand may be combined, e.g., by any convenient means such as mixing. The resulting rhodium/ligand complex catalyst may be introduced into the reactor, optionally with excess ligand. Alternatively, the rhodium precursor, (D) the solvent, and the ligand may be combined in the reactor with starting material (A) and/or (B), the vinyl-functional organosilicon compound; and the rhodium/ligand complex may form in situ. The relative amounts of ligand and rhodium precursor are sufficient to provide a molar ratio of ligand/Rh of 10/1 to 1/1, alternatively 5/1 to 1/1, alternatively 3/1 to 1/1, alternatively 2.5/1 to 1.5/1. In addition to the rhodium/ligand complex catalyst, excess (e.g., not complexed) ligand may be present in the reaction mixture. The excess ligand may be the same as, or different from, the ligand in the rhodium/ligand complex catalyst.


The amount of (C) the rhodium/ligand complex catalyst (catalyst) is sufficient to catalyze hydroformylation of (B) the vinyl-functional organosilicon compound. The exact amount of (C) the rhodium/ligand complex catalyst will depend on various factors including the type of vinyl-functional organosilicon compound selected for starting material (B), its exact vinyl content, and the reaction conditions such as temperature and pressure of starting material (A). However, the amount of (C) the rhodium/ligand complex catalyst may be sufficient to provide a rhodium metal concentration of at least 0.1 ppm, alternatively 0.15 ppm, alternatively 0.2 ppm, alternatively 0.25 ppm, and alternatively 0.5 ppm, based on the weight of (B) the vinyl-functional organosilicon compound. At the same time, the amount of (C) the rhodium/ligand complex catalyst may be sufficient to provide a rhodium metal concentration of up to 300 ppm, alternatively up to 100 ppm, alternatively up to 20 ppm, and alternatively up to 5 ppm, on the same basis. Alternatively, the amount of (C) the catalyst may be sufficient to provide 0.1 ppm to 300 ppm, alternatively 0.2 ppm to 100 ppm, alternatively, 0.25 ppm to 20 ppm, and alternatively 0.5 ppm to 5 ppm, based on the weight of (B) the vinyl-functional organosilicon compound.


The hydroformylation process reaction may run without additional solvents. Alternatively, the hydroformylation process reaction may be carried out with a solvent, for example to facilitate mixing and/or delivery of one or more of the starting materials described above, such as the (C) rhodium/ligand complex catalyst and/or starting material (B) the vinyl-functional organosilicon compound, when e.g., a vinyl-functional polyorganosilicate resin is selected for starting material (B). The solvent is exemplified by aliphatic or aromatic hydrocarbons, which can dissolve the starting materials, e.g., toluene, xylene, benzene, hexane, heptane, decane, cyclohexane, or a combination of two or more thereof. Additional solvents include THF, dibutyl ether, diglyme, and Texanol. Without wishing to be bound by theory, it is thought that solvent may be used to reduce the viscosity of the starting materials. The amount of solvent is not critical, however, when present, the amount of solvent may be 5% to 70% based on weight of starting material (B) the vinyl-functional organosilicon compound.


In the hydroformylation process described herein, the hydroformylation reaction in step 1) is performed at relatively low temperature. For example, step 1) may be performed at a temperature of at least 30° C., alternatively at least 50° C., and alternatively at least 70° C. At the same time, the temperature in step 1) may be up to 150° C.; alternatively up to 100° C.; alternatively up to 90° C., and alternatively up to 80° C. Without wishing to be bound by theory, it is thought that lower temperatures, e.g., 30° C. to 90° C., alternatively 40° C. to 90° C., alternatively 50° C. to 90° C., alternatively 60° C. to 90° C., alternatively 70° C. to 90° C., alternatively 80° C. to 90° C., alternatively 30° C. to 60° C., alternatively 50° C. to 60° C. may be desired for achieving high selectivity and ligand stability.


In the hydroformylation process described herein, step 1) may be performed at a pressure of at least 101 kPa (ambient), alternatively at least 206 kPa (30 psi), and alternatively at least 344 kPa (50 psi). At the same time, pressure in step 1) may be up to 6,895 kPa (1,000 psi), alternatively up to 1,379 kPa (200 psi), alternatively up to 1000 kPa (145 psi), and alternatively up to 689 kPa (100 psi). Alternatively, step 1) may be performed at 101 kPa to 6,895 kPa; alternatively 344 kPa to 1,379 kPa; alternatively 101 kPa to 1,000 kPa; and alternatively 344 kPa to 689 kPa. Without wishing to be bound by theory, it is thought that using relatively low pressures, e.g., < to 6,895 kPa in the process herein may be beneficial; the ligands described herein allow for low pressure hydroformylation processes, which have the benefits of lower cost and better safety than high pressure hydroformylation processes.


The hydroformylation process may be carried out in a batch, semi-batch, or continuous mode, using one or more suitable reactors, such as a fixed bed reactor, a fluid bed reactor, a continuous stirred tank reactor (CSTR), or a slurry reactor. The selection of (B) the vinyl-functional organosilicon compound, and (C) the catalyst, and whether (D) the solvent, is used may impact the size and type of reactor used. One reactor, or two or more different reactors, may be used. The hydroformylation process may be conducted in one or more steps, which may be affected by balancing capital costs and achieving high catalyst selectivity, activity, lifetime, and ease of operability, as well as the reactivity of the particular starting materials and reaction conditions selected, and the desired product.


Alternatively, the hydroformylation process may be performed in a continuous manner. For example, the process used may be as described in U.S. Pat. No. 10,023,516 except that the olefin feed stream and catalyst described therein are replaced with (B) the vinyl-functional organosilicon compound and (C) the rhodium/ligand complex catalyst, each described herein.


Step 1) of the hydroformylation process forms a hydroformylation reaction product comprising the propylaldehyde-functional organosilicon compound. The hydroformylation reaction product may further comprise additional materials, such as those which have either been deliberately employed, or formed in situ, during step 1) of the process. Examples of such materials that can also be present include unreacted (B) vinyl-functional organosilicon compound, unreacted (A) carbon monoxide and hydrogen gases, and/or in situ formed side products, such as ligand degradation products and adducts thereof, and high boiling liquid aldehyde condensation byproducts, as well as (D) a solvent, if employed. The term “ligand degradation product” includes but is not limited to any and all compounds resulting from one or more chemical transformations of at least one of the ligand molecules used in the process.


The process may further comprise one or more additional steps such as: 2) recovering (C) the rhodium/ligand complex catalyst from the reaction fluid comprising the propylaldehyde-functional organosilicon compound. Recovering (C) the rhodium/ligand complex catalyst may be performed by methods known in the art, including but not limited to adsorption and/or membrane separation (e.g., nanofiltration). Suitable recovery methods are as described, for example, in U.S. Pat. No. 5,681,473 to Miller, et al.; U.S. Pat. No. 8,748,643 to Priske, et al.; and 10,155,200 to Geilen, et al.


However, one benefit of the process described herein is that (C) the catalyst need not be removed and recycled. Due to the low level of Rh needed, it may be more cost effective not to recover and recycle (C) the catalyst; and the propylaldehyde-functional organosilicon compound produced by the process may be stable even when the catalyst is not removed. Therefore, alternatively, the process described above may be performed without step 2).


Alternatively, the process may further comprise 3) purification of the hydroformylation reaction product. For example, the propylaldehyde-functional organosilicon compound may be isolated from the additional materials, described above, by any convenient means such as stripping and/or distillation, optionally with reduced pressure.


Propylaldehyde-Functional Organosilicon Compound

The propylaldehyde-functional organosilicon compound described above is useful as a starting material in the process for preparing the propylimine-functional organosilicon compound and the aminopropyl-functional organosilicon compound. Starting material (E) is the propylaldehyde-functional organosilicon compound, which has, per molecule, at least one propylaldehyde-functional group covalently bonded to silicon. Alternatively, the propylaldehyde-functional organosilicon compound may have, per molecule, more than one propylaldehyde-functional group covalently bonded to silicon. The propylaldehyde-functional group covalently bonded to silicon may have formula:




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where G has empirical formula —C2H4—. G may be linear (—CH2CH—) or branched




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Alternatively, the propylaldehyde-functional organosilicon compound may be a combination of the propylaldehyde-functional organosilicon compound species in which some instances of group G are linear and some are branched. Alternatively, the propylaldehyde-functional organosilicon compound produced by the hydroformylation process described above may have most instances of G being linear. The propylaldehyde-functional organosilicon compound may be one propylaldehyde-functional organosilicon compound. Alternatively, two or more propylaldehyde-functional organosilicon compounds that differ from one another may be used in the process described herein. For example, the propylaldehyde-functional organosilicon compound may comprise one or both of a propylaldehyde-functional silane and a propylaldehyde-functional polyorganosiloxane.


The propylaldehyde-functional organosilicon compound may comprise (E1) a propylaldehyde-functional silane of formula (E1-1): RAldxSiR4(4-x), where each RAld is an independently selected group of the formula




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where G is as described above; and R4 and subscript x are as described above. Alternatively, each R4 may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms. Alternatively, subscript x may be 1 to 4.


Suitable propylaldehyde-functional silanes are exemplified by propylaldehyde-functional trialkylsilanes such as (propyl-aldehyde)-trimethylsilane and (propyl-aldehyde)-triethylsilane.


Alternatively, the propylaldehyde-functional organosilicon compound may comprise (E2) a propylaldehyde-functional polyorganosiloxane. Said propylaldehyde-functional polyorganosiloxane may be cyclic, linear, branched, resinous, or a combination of two or more thereof. Said propylaldehyde-functional polyorganosiloxane may comprise unit formula (E2-1):




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where each RAd is an independently selected propylaldehyde group of the formula




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as described above, and G, R4, Z. and subscripts a, b, c, d, e, f, g, and h are as described above.


Alternatively, (E2) the propylaldehyde-functional polyorganosiloxane may comprise (E2-2) a linear polydiorganosiloxane having, per molecule, at least one propylaldehyde-functional group; alternatively at least two propylaldehyde-functional groups (e.g., when in the formula (E2-1) for the propylaldehyde-functional polyorganosiloxane above, subscripts e=f=g=0). For example, said polydiorganosiloxane may comprise unit formula (E2-3): (R43SiO1/2)a(RAldR42SiO1/2)b(R42SiO2/2)c(RAldR4SiO2/2)d, where RAld and R4 are as described above, subscript a is 0, 1, or 2; subscript b is 0, 1, or 2, subscript c≥0, subscript d≥0, with the provisos that a quantity (b+d)≥1, a quantity (a+b)=2, and a quantity (a+b+c+d)≥2. Alternatively, in the unit formula (E2-3) for the linear propylaldehyde-functional polyorganosiloxane, above, the quantity (a+b+c+d) may be at least 3, alternatively at least 4, and alternatively >50. At the same time in said formula, the quantity (a+b+c+d) may be less than or equal to 10,000; alternatively less than or equal to 4,000; alternatively less than or equal to 2,000; alternatively less than or equal to 1,000; alternatively less than or equal to 500; alternatively less than or equal to 250. Alternatively, in the unit formula for the linear propylaldehyde-functional polyorganosiloxane, each R4 may be independently selected from the group consisting of alkyl and aryl; alternatively methyl and phenyl. Alternatively, each R4 in said formula may be an alkyl group; alternatively each R4 may be methyl.


Alternatively, the linear propylaldehyde-functional polydiorganosiloxane of unit formula (E2-3) may be selected from the group consisting of: unit formula (E2-4): (R42RAld SiO1/2)2(R42SiO2/2)m(R4RAld SiO2/2)n, unit formula (E2-5): (R43SiO1/2)2(R44SiO2/2)o(R4RAld SiO2/2)p, or a combination of both (E2-4) and (E2-5).


In formulae (E2-4) and (E2-5), each R4 and RAld are as described above. Subscript m may be 0 or a positive number. Alternatively, subscript m may be at least 2. Alternatively subscript m be 2 to 2,000. Subscript n may be 0 or a positive number. Alternatively, subscript n may be 0 to 2000. Subscript o may be 0 or a positive number. Alternatively, subscript o may be 0 to 2000. Subscript p is at least 2. Alternatively subscript p may be 2 to 2000.


Starting material (E2) may comprise a propylaldehyde-functional polydiorganosiloxane such as i) bis-dimethyl(propyl-aldehyde)siloxy-terminated polydimethylsiloxane, ii) bis-dimethyl(propyl-aldehyde)siloxy-terminated poly(dimethylsiloxane/methyl(propyl-aldehyde)siloxane), iii) bis-dimethyl(propyl-aldehyde)siloxy-terminated polymethyl(propyl-aldehyde)siloxane, iv) bis-trimethylsiloxy-terminated poly(dimethylsiloxane/methyl(propyl-aldehyde)siloxane), v) bis-trimethylsiloxy-terminated polymethyl(propyl-aldehyde)siloxane, vi) bis-dimethyl(propyl-aldehyde)siloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane/methyl(propyl-aldehyde)siloxane), vii) bis-dimethyl(propyl-aldehyde)siloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane), viii) bis-dimethyl(propyl-aldehyde)siloxy-terminated poly(dimethylsiloxane/diphenylsiloxane), ix) bis-phenyl,methyl,(propyl-aldehyde)-siloxy-terminated polydimethylsiloxane, and x) a combination of two or more of i) to ix).


Alternatively, (E2) the propylaldehyde-functional polyorganosiloxane may be cyclic, e.g., when in unit formula (E2-1), subscripts a=b=c=e=f=g=h=0. The (E2-6) cyclic propylaldehyde-functional polydiorganosiloxane may have unit formula (E2-7): (R4RAld SiO2/2)d, where RAld and R4 are as described above, and subscript d may be 3 to 12, alternatively 3 to 6, and alternatively 4 to 5. Examples of cyclic propylaldehyde-functional polydiorganosiloxanes include 2,4,6-trimethyl-2,4,6-tri(propyl-aldehyde)-cyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetra(propyl-aldehyde)-cyclotetrasiloxane, 2,4,6,8,10-pentamethyl-2,4,6,8,10-penta(propyl-aldehyde)-cyclopentasiloxane, and 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexa(propyl-aldehyde)-cyclohexasiloxane.


Alternatively, (E2-6) the cyclic propylaldehyde-functional polydiorganosiloxane may have unit formula (E2-8): (R42SiO2/2)c(R4RAld SiO2/2)d, where R4 and RAld are as described above, subscript c is >0 to 6 and subscript d is 3 to 12. Alternatively, in formula (E2-8), a quantity (c+d) may be 3 to 12. Alternatively, in formula (E2-8), c may be 3 to 6, and d may be 3 to 6.


Alternatively, (E2) the propylaldehyde-functional polyorganosiloxane may be (E2-9) oligomeric, e.g., when in unit formula (E2-1) above the quantity (a+b+c+d+e+f+g)≤50, alternatively ≤40, alternatively ≤30, alternatively ≤25, alternatively ≤20, alternatively ≤10, alternatively ≤5, alternatively ≤4, alternatively ≤3. The oligomer may be cyclic, linear, branched, or a combination thereof. The cyclic oligomers are as described above as starting material (E2-6).


Examples of linear propylaldehyde-functional polyorganosiloxane oligomers may have formula (E2-10):




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where R4 is as described above, each R2′ is independently selected from the group consisting of R4 and RAld, with the proviso that at least one R2′, per molecule, is RAld, and subscript z is 0 to 48. Alternatively, subscript z may be 0 to 4; alternatively 0 to 1; and alternatively 0. Alternatively, when z=0 in formula (E2-10), the propylaldehyde-functional polyorganosiloxane oligomer may have formula (E2-10a):




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where R4 and RAld are as described above. Examples of linear propylaldehyde-functional polyorganosiloxane oligomers include 1,3-di(propyl-aldehyde)-1,1,3,3-tetramethyldisiloxane; 1,1,1,3,3-pentamethyl-3-(propyl-aldehyde)-disiloxane; and 1,1,1,3,5,5,5-heptamethyl-3-(propyl-aldehyde)-trisiloxane.


Alternatively, the propylaldehyde-functional polyorganosiloxane oligomer may be branched. The branched oligomer may have general formula (E2-11): RAld SiR123, where RAld is as described above and each R12 is selected from R13 and —OSi(R14)3; where each R13 is a monovalent hydrocarbon group; where each R14 is selected from R13, —OSi(R15)3, and —[OSiR132]iiOSiR133; where each R15 is selected from R13, —OSi(R16)3, and —[OSiR132]iiOSiR133; where each R16 is selected from R13 and —[OSiR132]iiOSiR133; and where subscript ii has a value such that 0≤ii≤100. At least two of R12 may be —OSi(R14)3. Alternatively, all three of R12 may be —OSi(R14)3.


Alternatively, in formula (E2-11) when each R12 is R13, the branched polyorganosiloxane oligomer has the following structure (E2-11a):




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where RAld and R13 are as described above. Alternatively, in formula (E2-11a) each R13 may be methyl.


Alternatively, in formula (E2-11) when each R12 is —OSi(R14)3, each R14 may be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (E2-11b):




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where RAld and R15 are as described above. Alternatively, each R15 may be an R13, as described above, and each R13 may be methyl.


Alternatively, in formula (E2-11), when each R12 is —OSi(R14)3, one R14 may be R13 in each —OSi(R14)3 such that each R12 is —OSiR13(R14)2. Alternatively, two R14 in —OSiR13(R14)2 may each be —OSi(R15)3 moieties such that the branched propylaldehyde-functional polyorganosiloxane oligomer has the following structure (E2-11c):




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where RAld, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R13 may be methyl.


Alternatively, in formula (B2-11), one R12 may be R13, and two of R12 may be —OSi(R14)3. When two of R12 are —OSi(R14)3, and one R14 is R13 in each —OSi(R14)3 then two of R12 are —OSiR13(R14)2. Alternatively, each R14 in —OSiR13(R14)2 may be —OSi(R15)3 such that the branched polyorganosiloxane oligomer has the following structure (E2-11d):




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where RAld, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R13 may be methyl. Alternatively, the propylaldehyde-functional branched polyorganosiloxane may have 3 to 16 silicon atoms per molecule, alternatively 4 to 16 silicon atoms per molecule, and alternatively 4 to 10 silicon atoms per molecule. Examples of propylaldehyde-functional branched polyorganosiloxane oligomers include 3-(3,3,3-trimethyl-1-λ2-disiloxaneyl)propanal (which can also be named propyl-aldehyde-tris(trimethyl)siloxy)silane), which has formula:




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3-(1,3,5,5,5-pentamethyl-1λ3,3λ3-trisiloxaneyl)propanal (which can also be named methyl-(propyl-aldehyde)-di((1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)oxy)-silane), which has formula



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3-(3,5,5,5-tetramethyl-1λ2,3λ3-trisiloxaneyl)propanal (which can also be named (propyl-aldehyde)-tris((1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)oxy)-silane), which has formula



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Alternatively, (E2) the propylaldehyde-functional polyorganosiloxane may be branched, such as the branched oligomer described above and/or a branched propylaldehyde-functional polyorganosiloxane that may have, e.g., more propylaldehyde groups per molecule and/or more polymer units than the branched oligomer described above (e.g., in formula (E2-1) when the quantity (a+b+c+d+e+f+g)>50). The branched propylaldehyde-functional polyorganosiloxane may have (in formula (E2-1)) a quantity (e+f+g) sufficient to provide >0 to 5 mol % of trifunctional and/or quadrifunctional units to the branched propylaldehyde-functional polyorganosiloxane.


For example, the branched propylaldehyde-functional polyorganosiloxane may comprise a Q branched polyorganosiloxane of unit formula (E2-13): (R43SiO1/2)q(R42RAld SiO1/2)r(R42SiO2/2)s(SiO4/2)t, where R4 and RAMd are as described above, and subscripts q, r, s, and t have average values such that 2≥q≥0, 4≥r≥0, 995≥s≥4, t=1, (q+r)=4, and (q+r+s+t) has a value sufficient to impart a viscosity >170 mPa·s measured by rotational viscometry (as described below with the test methods) to the branched polyorganosiloxane. Alternatively, viscosity may be >170 mPa·s to 1000 mPa·s, alternatively >170 to 500 mPa·s, alternatively 180 mPa·s to 450 mPa·s, and alternatively 190 mPa·s to 420 mPa·s.


Alternatively, the branched propylaldehyde-functional polyorganosiloxane may comprise formula (E2-14): [RAldR42Si—(O—SiR42)x—O](4-w)—Si—[O—(R42SiO)vSiR43]w, where RAld and R4 are as described above; and subscripts v, w, and x have values such that 200≥v≥1, 2≥w≥0, and 200≥x≥1. Alternatively, in this formula (E2-14), each R4 is independently selected from the group consisting of methyl and phenyl.


Alternatively, the branched propylaldehyde-functional polyorganosiloxane for starting material (E2-11) may comprise a T branched polyorganosiloxane (silsesquioxane) of unit formula (E2-15): (R43SiO1/2)aa(RAldR42SiO1/2)bb(R4SiO2/2)cc(RAldR4SiO2/2)ee(R4SiO3/2)dd, where R4 and RAld are as described above, subscript aa≥0, subscript bb>0, subscript cc is 15 to 995, subscript dd>0, and subscript ee≥0. Subscript aa may be 0 to 10. Alternatively, subscript aa may have a value such that: 12≥aa≥0; alternatively 10≥aa≥0; alternatively 7≥aa≥0; alternatively 5≥aa≥0; and alternatively 3≥aa≥0. Alternatively, subscript bb≥1. Alternatively, subscript bb≥3. Alternatively, subscript bb may have a value such that: 12≥bb>0; alternatively 12≥bb≥3; alternatively 10≥bb>0; alternatively 7≥bb>1; alternatively 5≥bb≥2; and alternatively 7≥bb≥3. Alternatively, subscript cc may have a value such that: 800≥cc≥15; and alternatively 400≥cc≥15. Alternatively, subscript ee may have a value such that: 800≥ee≥0; 800≥ee≥15; and alternatively 400≥ee≥15. Alternatively, subscript ee may b 0. Alternatively, a quantity (cc+ee) may have a value such that 995≥(cc+ee)≥15. Alternatively, subscript dd≥1. Alternatively, subscript dd may be 1 to 10. Alternatively, subscript dd may have a value such that: 10≥dd>0; alternatively 5≥dd>0; and alternatively dd=1. Alternatively, subscript dd may be 1 to 10, alternatively subscript dd may be 1 or 2. Alternatively, when subscript dd=1, then subscript bb may be 3 and subscript cc may be 0. The values for subscript bb may be sufficient to provide the silsesquioxane of unit formula (E2-15) with an aldehyde content of 0.1% to 1%, alternatively 0.2% to 0.6%, based on the weight of the silsesquioxane.


Alternatively, (E2) the propylaldehyde-functional polyorganosiloxane may comprise a propylaldehyde-functional polyorganosiloxane resin, such as a propylaldehyde-functional polyorganosilicate resin and/or a propylaldehyde-functional silsesquioxane resin. Such resins may be prepared, for example, by hydroformylating a vinyl-functional polyorganosiloxane resin, as described above. The propylaldehyde-functional polyorganosilicate resin comprises monofunctional units (“M′” units) of formula RM′3SiO1/2 and tetrafunctional silicate units (“Q” units) of formula SiO4/2, where each RM′ may be independently selected from the group consisting of R4 and RAld as described above. Alternatively, each RM′ may be selected from the group consisting of an alkyl group, a propylaldehyde-functional group of the formula shown above, and an aryl group. Alternatively, each RM′ may be selected from methyl, (propyl-aldehyde) and phenyl. Alternatively, at least one-third, alternatively at least two thirds of the RM′ groups are methyl groups. Alternatively, the M′ units may be exemplified by (Me3SiO1/2), (Me2PhSiO1/2), and (Me2RAld SiO1/2). The polyorganosilicate resin is soluble in solvents such as those described herein as starting material (D), exemplified by liquid hydrocarbons, such as benzene, ethylbenzene, toluene, xylene, and heptane, or in liquid non-functional organosilicon compounds such as low viscosity linear and cyclic polydiorganosiloxanes.


When prepared, the polyorganosilicate resin comprises the M′ and Q units described above, and the polyorganosiloxane further comprises units with silicon bonded hydroxyl groups, and/or hydrolyzable groups, described by moiety (ZO1/2), above, and may comprise neopentamer of formula Si(OSiRM′3)4, where RM′ is as described above, e.g., the neopentamer may be tetrakis(trimethylsiloxy)silane. 29Si NMR and 13C NMR spectroscopies may be used to measure hydroxyl and alkoxy content and molar ratio of M′ and Q units, where said ratio is expressed as {M′(resin)}/{Q(resin)}, excluding M′ and Q units from the neopentamer. M′/Q ratio represents the molar ratio of the total number of triorganosiloxy groups (M′ units) of the resinous portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. M′/Q ratio may be 0.5/1 to 1.5/1, alternatively 0.6/1 to 0.9/1.


The Mn of the polyorganosilicate resin depends on various factors including the types of hydrocarbon groups represented by RM′ that are present. The Mn of the polyorganosilicate resin refers to the number average molecular weight measured using GPC, when the peak representing the neopentamer is excluded from the measurement. The Mn of the polyorganosilicate resin may be 1,500 Da to 30,000 Da, alternatively 1,500 Da to 15,000 Da; alternatively>3,000 Da to 8,000 Da. Alternatively, Mn of the polyorganosilicate resin may be 3,500 Da to 8,000 Da.


Alternatively, the polyorganosilicate resin may comprise unit formula (E2-17): (R43SiO1/2)mm(R42RAld SiO1/2)nn(SiO4/2)oo(ZO1/2)h, where Z, R4, and RAld, and subscript h are as described above and subscripts mm, nn and oo have average values such that mm≥0, nn>0, oo>0, and 0.5≥(mm+nn)/oo≤4. Alternatively, 0.6≤(mm+nn)/oo≥4; alternatively 0.7≤(mm+nn)/oo≥4, and alternatively 0.8≤(mm+nn)/oo≤4.


Alternatively, (E2) the propylaldehyde-functional polyorganosiloxane may comprise (E2-18) a propylaldehyde-functional silsesquioxane resin, i.e., a resin containing trifunctional (T′) units of unit formula:




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where R4 and RAld are as described above, subscript f>1, 2<(e+f)<10,000; 0<(a+b)/(e+f)<3; 0<(c+d)/(e+f)<3; and 0<h/(e+f)<1.5. Alternatively, the propylaldehyde-functional silsesquioxane resin may comprise unit formula (E2-19): (R4SiO3/2)e(RAldSiO3/2)f(ZO1/2)h, where R4, RAld, Z, and subscripts h, e and f are as described above. Alternatively, the propylaldehyde-functional silsesquioxane resin may further comprise difunctional (D′) units of formulae (R42SiO2/2)c(R4RAldSiO2/2)d in addition to the T units described above, i.e., a D′T′ resin, where subscripts c and d are as described above. Alternatively, the propylaldehyde-functional silsesquioxane resin may further comprise monofunctional (M′) units of formulae (R43SiO1/2)a(R42RAldSiO1/2)b, i.e., an M′D′T′ resin, where subscripts a and b are as described above for unit formula (E2-1).


Alternatively, starting material (E) the propylaldehyde-functional organosilicon compound may comprise unit formula (E3-1): [(R1(3-gg)RAldggSi)ffNH(3-ff)]hh, where RAld is the propylaldehyde-group as described above; each R′ is independently selected from the group consisting of an alkyl group and an aryl group as described above; each subscript ff is independently 1 or 2 as described above; subscript gg is independently 0, 1, or 2 as described above; and subscript h has a value such that 1<hh<10 as described above.


Starting material (E) may be any one of the propylaldehyde-functional organosilicon compounds described above (whether made via the hydroformylation reaction process described herein or some other method). Alternatively, starting material (E) may comprise a mixture of two or more of the propylaldehyde-functional organosilicon compounds.


Alternatively, in the process described herein starting material (E) may be a hydrolytically unstable propylaldehyde-functional organosilicon compound. The hydrolytically unstable propylaldehyde-functional organosilicon compound may be, for example, any one of (E1) the propylaldehyde-functional silanes and/or (E2) the propylaldehyde-functional polyorganosiloxanes of any of the formulas shown above, where at least one R4 is a hydrocarbonoxy group or an acyloxy group; any (E3) propylaldehyde-functional silazane; or any propylaldehyde-functional polyorganosiloxane oligomer of formula (E2-10a) such as 1,3-di(propyl-aldehyde)-1,1,3,3-tetramethyldisiloxane or (E2-11a) such as 1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)-3-vinyltrisiloxane, shown above.


Preparing the Propylimine-Functional Organosilicon Compound and the Aminopropyl-Functional Organosilicon Compound

The process for preparing the propylimine-functional organosilicon compound comprises:

    • I) combining, under conditions to effect a dehydrative imine generation reaction, starting materials comprising
      • (E) the propylaldehyde-functional organosilicon compound described above, and
      • (F1) a primary amine source;
      • optionally (G) a hydrogenation catalyst; and
      • optionally (J) a solvent;
      • with the proviso that step I) is performed in the absence of hydrogen when (G) the hydrogenation catalyst is present in step I);
      • thereby forming a reaction product comprising (L) a propylimine-functional organosilicon compound and water;
    • optionally II) removing the water generated by the dehydrative imine generation reaction in step I); and
    • optionally isolating (L) the propylimine-functional organosilicon compound. The propylimine-functional organosilicon compound may be isolated by any convenient means such as stripping and/or distillation of the reaction product, and the propylimine-functional organosilicon compound may be used for other purposes than those described below.


      Alternatively, (L) the propylimine-functional organosilicon compound may be used to prepare the aminopropyl-functional organosilicon compound when the process further comprises:
    • III) combining, under conditions to catalyze reductive amination reaction, starting materials comprising
      • (L) the propylimine-functional organosilicon compound described above,
      • (F2) ammonia,
      • optionally (G) a hydrogenation catalyst,
      • (H) hydrogen, and
      • optionally (J) a solvent; thereby forming a reductive amination reaction product comprising the aminopropyl-functional organosilicon compound.
      • with the proviso that (G) the hydrogenation catalyst is added in at least one of step I) and step III).


The process may optionally further comprise, before step I), 1) combining, under conditions to catalyze hydroformylation reaction, starting materials comprising (A) the gas comprising hydrogen and carbon monoxide, (B) the vinyl-functional organosilicon compound, and (C) the rhodium/ligand complex catalyst, thereby forming a hydroformylation reaction product comprising the propylaldehyde-functional organosilicon compound as described above. The process may optionally further comprise, before step I) and after step 1), step 2) recovering (C) the rhodium/ligand complex catalyst from the reaction product comprising the propylaldehyde-functional organosilicon compound. However, step 2) is optional and may be unnecessary. For example, when hydroformylation is used to prepare (E) the propylaldehyde-functional organosilicon compound, the hydroformylation reaction catalyst may be unnecessary to remove because, without wishing to be bound by theory, it is thought that the amount of catalyst is not cost effective to remove and/or the selection and amount of catalyst do not detrimentally impact the dehydrative imine generation reaction or the reductive amination reaction. The process may optionally further comprise, before step I) and after step 1) or step 2) (when present), step 3) purifying the hydroformylation reaction product; thereby isolating (E) the propylaldehyde-functional organosilicon compound from the additional materials, as described above. However, this step 3) is optional, and may be unnecessary, for example, when a solvent is used for hydroformylation reaction to prepare (E) the propylaldehyde-functional organosilicon compound, and the same solvent will be used in a step later in the process.


Step I) Protecting the Aldehyde

In step I) of the process described above, a dehydrative imine generation reaction occurs to protect the aldehyde group and form an imine group. In step I), starting materials comprising (E) the propylaldehyde-functional organosilicon compound and (F1) a primary amine source may be combined by any convenient means, such as mixing. Mixing may be performed by any convenient means, at e.g., RT and ambient pressure and atmosphere. Time for mixing is sufficient for an imine group to form from the aldehyde group under the conditions selected. Step I) may be performed in a batch mode or a continuous mode. Time is not critical and is sufficient for the imine group to form, such as 1 second to 1 hour.


(F) Amine Sources

In the process described herein, (F1) a primary amine source is used in step I). The primary amine source may be any primary amine source that is inexpensive and separable from the aminopropyl-functional organosilicon compound to be prepared by the process. The primary amine source may be an organic primary amine. The organic primary amine may have formula: R18NH2, where R18 is an alkyl group of 1 to 18 carbon atoms or an aryl group of 6 to 18 carbon atoms. Suitable alkyl groups for R18 may be linear, branched, cyclic, or combinations of two or more thereof. The alkyl groups are exemplified by methyl, ethyl, propyl (including n-propyl and/or isopropyl), butyl (including n-butyl, tert-butyl, sec-butyl, and/or isobutyl); pentyl, hexyl, heptyl, octyl, decyl, dodecyl, undecyl, and octadecyl (and branched isomers having 5 to 18 carbon atoms), and the alkyl groups are further exemplified by cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Suitable aryl groups for R18 may be, for example, phenyl, tolyl, xylyl, phenyl ethyl, and benzyl. Alternatively, the alkyl group for R18 may be selected from the group consisting of ethyl, propyl and butyl; alternatively ethyl and propyl; alternatively propyl and butyl. Alternatively, the alkyl group for R18 may be propyl. Alternatively, R18 may be an aryl group, and alternatively R18 may be benzyl. Alternatively, the organic primary amine may have more than one primary amine group per molecule. Organic primary amines are known in the art and are commercially available. For example, ethyl amine, propyl amine, n-butyl amine, isobutyl amine, and benzyl amine are available from various sources, such as Acros Organics or Sigma Aldrich, Inc. of St. Louis, Missouri, USA. Alternatively, the primary amine source may comprise a primary amino-functional organosilicon compound. The primary amino-functional organosilicon compound used as the primary amine source in step I) may be any primary amino-functional organosilicon compound, e.g., the primary amine source may have the same formula as primary amino-functional organosilicon compound to be prepared by this process. For example, the primary amine source may be 2-aminopropyltrimethylsilane, 3,3′-(1,1,3,3,-tetramethyldisiloxane-1,3-diyl)propan-diamine. The formation of an imine-functional organosilicon compound using a primary amino-functional organosilicon compound as the primary amine source is illustrated below in Scheme 1.




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The primary amine source used in step I) may be used in a superstoichiometric amount of amine functionality with respect to the aldehyde-functionality of (E) the propylaldehyde-functional organosilicon compound. For example, the primary amine source may be used in an amount sufficient to provide 10:1 to 1:1 molar ratio of amine groups:aldehyde groups.


Propylimine-Functional Organosilicon Compound

The propylimine-functional organosilicon compound prepared in step I) of the process described above has, per molecule, at least one propylimine-functional group covalently bonded to silicon. Alternatively, the propylimine-functional organosilicon compound may have, per molecule, more than one propylimine-functional group covalently bonded to silicon. This propylimine-functional group, R1, may have formula:




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where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms, as described and exemplified above, and R19 is selected from R18 (the alkyl group or the aryl group as described above when the organic primary amine is used as the primary amine source) and an organosilicon moiety (when the amino-functional organosilicon compound is used as the primary amine source). The propylimine-functional organosilicon compound may have any of the formulas described above for (E) the propylaldehyde-functional organosilicon compound, with the proviso that at least one RAld per molecule is replaced with R1. Alternatively, all, or substantially all, instances of RAld may be replaced with R1.


The propylimine-functional organosilicon compound may comprise (L1) a propylimine-functional silane of formula (L1-1): R1xSiR4(4-X), where R1, R4 and subscript x are as described above.


Alternatively, the propylimine-functional organosilicon compound may comprise (L2) a propylimine-functional polyorganosiloxane. Said propylimine-functional polyorganosiloxane may be cyclic, linear, branched, resinous, or a combination of two or more thereof. Said propylimine-functional polyorganosiloxane may comprise unit formula (L2-1): (R43SiO1/2)a(R42RISiO1/2)b(R42SiO2/2)c(R4RISiO2/2)d(R4SiO3/2)e(RISiO3/2)f(SiO4/2)g(ZO1/2)h; where each RI is an independently selected imine group of the formula described above, and R4, Z, and subscripts a, b, c, d, e, f, g, and h are as described above for formula (B2-1).


Alternatively, (L2) the propylimine-functional polyorganosiloxane may comprise (L2-2) a linear polydiorganosiloxane having, per molecule, at least one propylimine-functional group; alternatively at least two propylimine-functional groups (e.g., when in the formula (L2-1) for the propylimine-functional polyorganosiloxane above, subscripts e=f=g=0). For example, said polydiorganosiloxane may comprise unit formula (L2-3): (R43SiO1/2)a(R1R42SiO1/2)b(R42SiO2/2)c(R1R4SiO2/2)d, where R1 is as described above, and R4 and are subscripts a, b, c, and d are as described above for formula (E2-3).


Alternatively, the linear propylimine-functional polydiorganosiloxane of unit formula (L2-3) may be selected from the group consisting of: unit formula (L2-4): (R42R1SiO1/2)2(R42SiO2/2)m(R4R1SiO2/2)n, unit formula (L2-5): (R43SiO1/2)2(R42SiO2/2)o(R4RISiO2/2)p, or a combination of both (L2-4) and (L2-5).


In formulae (L2-4) and (L2-5), RI is as described above, and R4 and subscripts m, n, o, and p are as described above for formulae (E2-4) and (E2-5).


Alternatively, (L2) the propylimine-functional polyorganosiloxane may be cyclic, e.g., when in unit formula (L2-1), subscripts a=b=c=e=f=g=h=0. The (L2-6) cyclic propylimine-functional polydiorganosiloxane may have unit formula (L2-7): (R4RISiO2/2)d, where RI and R4 are as described above, and subscript d may be 3 to 12, alternatively 3 to 6, and alternatively 4 to 5.


Alternatively, (L2-6) the cyclic imine-functional polydiorganosiloxane may have unit formula (L2-8): (R42SiO2/2)c(R4RISiO1/2)a, where R4 and RI are as described above, subscript c is >0 to 6 and subscript d is 3 to 12. Alternatively, in formula (L2-8), a quantity (c+d) may be 3 to 12. Alternatively, in formula (L2-8), c may be 3 to 6, and d may be 3 to 6.


Alternatively, (L2) the imine-functional polyorganosiloxane may be (L2-9) oligomeric, e.g., when in unit formula (L2-1) above the quantity (a+b+c+d+e+f+g)≤50, alternatively ≤40, alternatively ≤30, alternatively ≤25, alternatively ≤20, alternatively ≤10, alternatively ≤5, alternatively ≤4, alternatively ≤3. The oligomer may be cyclic, linear, branched, or a combination thereof. The cyclic oligomers are as described above as starting material (L2-6).


Examples of linear propylimine-functional polyorganosiloxane oligomers may have formula (L2-10):




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where R4 is as described above, each R2′″ is independently selected from the group consisting of R4 and RI, with the proviso that at least one R2′″, per molecule, is RI, and subscript z is 0 to 48. Alternatively, subscript z may be 0 to 4; alternatively 0 to 1; and alternatively 0. Alternatively, when z=0 in formula (L2-10), the propylimine-functional polyorganosiloxane oligomer may have formula (L2-10a):




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where R4 and RI areas described above.


Alternatively, the propylimine-functional polyorganosiloxane oligomer may be branched. The branched oligomer may have general formula (L2-11): RISiR123, where R1 is as described above and each R12 is selected from R13 and —OSi(R14)3; where each R13 is a monovalent hydrocarbon group; where each R14 is selected from R13, —OSi(R15)3, and —[OSiR132]iiOSiR133; where each R15 is selected from R13, —OSi(R16)3, and —[OSiR132]iiOSiR133; where each R16 is selected from R13 and —[OSiR132]iiOSiR133; and where subscript ii has a value such that 0≤ii≤100. At least two of R12 may be —OSi(R14)3. Alternatively, all three of R12 may be —OSi(R14)3.


Alternatively, in formula (L2-11) when each R12 is R13, the branched polyorganosiloxane oligomer has the following structure (L2-11a):




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where RI and R13 are as described above. Alternatively, in formula (L2-11a) each R13 may be methyl.


Alternatively, in formula (L2-11) when each R12 is —OSi(R14)3, each R14 may be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (L2-11b):




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where RI and R15 are as described above. Alternatively, each R15 may be an R13, as described above, and each R13 may be methyl.


Alternatively, in formula (L2-11), when each R12 is —OSi(R14)3, one R may be R13 in each —OSi(R14)3 such that each R12 is —OSiR13(R14)2. Alternatively, two R14 in —OSiR13(R14)2 may each be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (L2-11c):




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where R1, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R3 may be methyl.


Alternatively, in formula (L2-11), one R may be R13, and two of R12 may be —OSi(R14)3. When two of R12 are —OSi(R14)3, and one R14 is R13 in each —OSi(R14)3 then two of R12 are —OSiR13(R14)2. Alternatively, each R14 in —OSiR13(R14)2 may be —OSi(R15)3 such that the branched polyorganosiloxane oligomer has the following structure (L2-11 d):




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here RI, R13, and R15 are as described above. Alternatively, each R5 may be an R13, and each R13 may be methyl. Alternatively, the branched polyorganosiloxane may have 3 to 16 silicon atoms per molecule, alternatively 4 to 16 silicon atoms per molecule, and alternatively 4 to 10 silicon atoms per molecule. Examples of imine-functional branched polyorganosiloxane oligomers include (E)-N-butyl-3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-imine, which has formula:




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and (E)-3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)-N-propylpropan-1-imine, which has formula




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Alternatively, (L2) the propylimine-functional polyorganosiloxane may be branched, such as the branched oligomer described above and/or a branched propylimine-functional polyorganosiloxane that may have, e.g., more propylimine groups per molecule and/or more polymer units than the branched oligomer described above (e.g., in formula (L2-1) when the quantity (a+b+c+d+e+f+g)>50). The branched propylimine-functional polyorganosiloxane may have (in formula (L2-1)) a quantity (e+f+g) sufficient to provide >0 to 5 mol % of trifunctional and/or quadrifunctional units to the branched propylimine-functional polyorganosiloxane.


For example, the branched propylimine-functional polyorganosiloxane may comprise a Q branched polyorganosiloxane of unit formula (L2-13): (R43SiO1/2)q(R42RISiO1/2)r(R42SiO2/2)s(SiO4/2)t, where RI is as described above, and R4 and subscripts q, r, s, and t are as described above for (E2-13).


Alternatively, the branched propylimine-functional polyorganosiloxane may comprise formula (L2-14): [RIR42Si—(O—SiR42)x—O](4-w)—Si—[O—(R42SiO)vSiR43]w, where RI is as described above, and R4 and subscripts v, w, and x are as described above with respect to formula (E2-14). Alternatively, in this formula (L2-14), each R4 is independently selected from the group consisting of methyl and phenyl, and each R1 has the formula above, wherein G has 2, 3, or 6 carbon atoms.


Alternatively, the branched propylimine-functional polyorganosiloxane for (L2-11) may comprise a T branched polyorganosiloxane (silsesquioxane) of unit formula (L2-15): (R43SiO1/2)aa(RIR42SiO1/2)bb(R42SiO2/2)cc(RIR4SiO2/2)ee(R4SiO3/2)dd, where R1 is as described above, and R4 and subscripts aa, bb, cc, dd, and ee are as described above for unit formula (E2-15).


Alternatively, (L2) the propylimine-functional polyorganosiloxane may comprise a propylimine-functional polyorganosiloxane resin, such as a propylimine-functional polyorganosilicate resin and/or a propylimine-functional silsesquioxane resin. The propylimine-functional polyorganosilicate resin comprises monofunctional units (“M′″” units) of formula RM′″3SiO1/2 and tetrafunctional silicate units (“Q” units) of formula SiO4/2, where each RM′″ be independently selected from the group consisting of R4 and RI as described above. Alternatively, each RM′″ may be selected from the group consisting of an alkyl group, a propylimine-functional group of the formula for RI shown above, and an aryl group. The polyorganosilicate resin is soluble in solvents such as those described herein as starting material (D), exemplified by liquid hydrocarbons, such as benzene, ethylbenzene, toluene, xylene, and heptane, or in liquid non-functional organosilicon compounds such as low viscosity linear and cyclic polydiorganosiloxanes.


The propylimine-functional polyorganosilicate resin comprises the M′″ and Q units described above, and the polyorganosilicate resin further comprises units with silicon bonded hydroxyl groups, and/or hydrolyzable groups, described by moiety (ZO1/2), above, and may comprise neopentamer of formula Si(OSiRM′″3)4, where RM′″ is as described above, e.g., the neopentamer may be tetrakis(trimethylsiloxy)silane. 29Si NMR and 13C NMR spectroscopies may be used to measure hydroxyl and alkoxy content and molar ratio of M′″ and Q units, where said ratio is expressed as {M′″(resin)}/{Q(resin)}, excluding M′″ and Q units from the neopentamer. M′″/Q ratio represents the molar ratio of the total number of triorganosiloxy groups (M′″ units) of the resinous portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. M′″/Q ratio may be 0.5/1 to 1.5/1, alternatively 0.6/1 to 0.9/1.


The Mn of the polyorganosilicate resin depends on various factors including the types of hydrocarbon groups represented by RM′″ that are present. The Mn of the polyorganosilicate resin refers to the number average molecular weight measured using GPC, when the peak representing the neopentamer is excluded from the measurement. The Mn of the polyorganosilicate resin may be 1,500 Da to 30,000 Da, alternatively 1,500 Da to 15,000 Da; alternatively >3,000 Da to 8,000 Da. Alternatively, Mn of the polyorganosilicate resin may be 3,500 Da to 8,000 Da.


Alternatively, the polyorganosilicate resin may comprise unit formula (L2-17): (R43SiO1/2)mm(R42R1SiO1/2)nn(SiO4/2)oo(ZO1/2)h, where Z, R4, and RI, and subscript h are as described above and subscripts mm, nn and oo have average values such that mm≥0, nn>0, oo>0, and 0.5≤(mm+nn)/oo≤4. Alternatively, 0.6≤(mm+nn)/oo≤4; alternatively 0.7≤(mm+nn)/oo≤4, and alternatively 0.8≤(mm+nn)/oo≤4.


Alternatively, (L2) the propylimine-functional polyorganosiloxane may comprise (L2-18) a propylimine-functional silsesquioxane resin, i.e., a resin containing trifunctional (T′″) units of unit formula: (R43SiO1/2)a(R42R1SiO1/2)b(R42SiO2/2)c(R4RISiO2/2)d(R4SiO3/2)e(RISiO3/2)f(ZO1/2)h; where R4 and RI are as described above, subscript f>1, 2<(e+f)<10,000; 0<(a+b)/(e+f)<3; 0<(c+d)/(e+f)<3; and 0<h/(e+f)<1.5. Alternatively, the propylimine-functional silsesquioxane resin may comprise unit formula (L2-19): (R4SiO3/2)e(R1SiO3/2)f(ZO2)h, where R4, RI, Z, and subscripts h, e and f are as described above. Alternatively, the propylimine-functional silsesquioxane resin may further comprise difunctional (D′″) units and said imine-functional silsesquioxane resin may comprise units of formulae (R42SiO2/2)c(R4RISiO2/2)a in addition to the T units described above, i.e., a D′″T′″ resin, where subscripts c and d are as described above. Alternatively, the propylimine-functional silsesquioxane resin may further comprise monofunctional (M′″) units of formulae (R43SiO1/2)a(R42RISiO1/2)b, i.e., an M′″D′″T′″ resin, where subscripts a and b are as described above for unit formula (E2-1).


Alternatively, (L) the propylimine-functional organosilicon compound may comprise unit formula (L3-1): [(R1(3-gg)RIggSi)ffNH(3-ff)]hh, where RI is the propylimine-group as described above; each R1 is independently selected from the group consisting of an alkyl group and an aryl group as described above; each subscript ff is independently 1 or 2 as described above; subscript gg is independently 0, 1, or 2 as described above; and subscript h has a value such that 1<hh<10 as described above.


The propylimine-functional organosilicon compound, (L), prepared in step I) and which can be used in step III) of the process described herein may be any one of the propylimine-functional organosilicon compounds described above. Alternatively, (L) the propylimine-functional organosilicon compound may comprise a mixture of two or more of the propylimine-functional organosilicon compounds.


Alternatively, in the process described herein (L) the propylimine-functional organosilicon compound may be a hydrolytically unstable propylimine-functional organosilicon compound. The hydrolytically unstable propylimine-functional organosilicon compound may be, for example, any one of (L1) the propylimine-functional silanes and/or (L2) the propylimine-functional polyorganosiloxanes of any of the formulas shown above, where at least one R4 is a hydrocarbonoxy group or an acyloxy group; any (L3) propylimine-functional silazane; or any propylimine-functional polyorganosiloxane oligomer of formula (L2-10a) or (L2-11a) such as (E)-N-butyl-3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-imine or (E)-3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)-N-propylpropan-1-imine, shown above.


Step II) Drying

The process described above may optionally further comprise step II) removing water generated by the dehydrative imine generation reaction in step I). Step II) may be performed during and/or after step I); during and/or after step III), or a combination thereof. Alternatively, step II) may be present and performed during and/or after step I), e.g., when a hydrolytically unstable propylaldehyde-functional organosilicon compound is used and/or a hydrolytically unstable propylmine-functional organosilicon compound or hydrolytically unstable aminopropyl-functional organosilicon compound will be formed during the process.


In step II), water may be removed by any convenient means, such as stripping, distillation, and/or contacting the reaction mixture in step I) and/or the reaction product of step I) with (K) a drying agent. The drying agent may comprise an adsorbent, which may comprise an inorganic particulate. The adsorbent may have a particle size of 10 micrometers or less, alternatively 5 micrometers or less. The adsorbent may have average pore size sufficient to adsorb water, for example 10 Å (Angstroms) or less, alternatively 5 Å or less, and alternatively 3 Å or less. Examples of adsorbents include zeolites such as chabasite, mordenite, and analcite; molecular sieves such as alkali metal alumino silicates, silica gel, silica-magnesia gel, activated carbon, activated alumina, calcium oxide, and combinations thereof.


Examples of commercially available adsorbents include dry molecular sieves, such as 3 Å (Angstrom) molecular sieves, which are commercially available from Grace Davidson under the trademark SYLOSIV™ and from Zeochem of Louisville, Kentucky, U.S.A. under the trade name PURMOL, and 4 Å molecular sieves such as Doucil zeolite 4A available from Ineos Silicas of Warrington, England. Other useful molecular sieves include MOLSIV ADSORBENT TYPE 13X, 3A, 4A, and 5A, all of which are commercially available from UOP of Illinois, U.S.A.; SILIPORITE NK 30AP and 65×P from Atofina of Philadelphia, Pennsylvania, U.S.A.; and molecular sieves available from W. R. Grace of Maryland, U.S.A.


Alternatively, the drying agent may comprise a chemical that complexes with water, such as calcium chloride (CaCl2)), sodium sulfate (Na2SO4) calcium sulfate (CaSO4), or magnesium sulfate (MgSO4), all of which are commercially available.


The amount of the drying agent is not specifically restricted and depends on various factors including the type of the drying agent selected. One skilled in the art would be able to select an appropriate drying agent and conditions for removing water in step II). When the drying agent is used, the process described herein may further comprise removing the drying agent before step III). The drying agent may then be removed by any convenient means, such as filtration. Alternatively, the drying agent may be used during and/or after step III). The drying agent may then be removed after step III).


The process for making the aminopropyl-functional organosilicon compound may optionally further comprise, before step III), an additional step of pre-treating (G) the hydrogenation catalyst. Pre-treating may be performed to activate the catalyst and/or increase the activity of the catalyst. Pre-treating may be performed by any convenient means, such as exposing the hydrogenation catalyst to hydrogen before beginning the reductive amination reaction in step III). For example, a packed bed of hydrogenation catalyst may be purged with hydrogen before introducing (L) the propylimine-functional organosilicon compound and (F2) the ammonia.


In step III) of the process, (F2) ammonia, which has formula NH3, e.g., anhydrous ammonia is used. Ammonia is known in the art and commercially available from various sources, including Air Products of Allentown, Pennsylvania, USA. The amount of (F2) ammonia used in step III) may be sufficient to provide a >1:1, alternatively ≥5:1, alternatively 10:1 to 40:1 molar ratio of ammonia:imine groups.


(G) Hydrogenation Catalyst

The hydrogenation catalyst used in step III) of the process for preparing the aminopropyl-functional organosilicon compound may be a heterogeneous hydrogenation catalyst, a homogenous hydrogenation catalyst, or a combination thereof. Alternatively, the hydrogenation catalyst may be a heterogeneous hydrogenation catalyst. Suitable heterogeneous hydrogenation catalysts comprise a metal selected from the group consisting of cobalt (Co), copper (Cu), iron (Fe), nickel (Ni), iridium (Ir), palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), and a combination of two or more thereof. Alternatively, the hydrogenation catalyst may comprise Co, Cu, Ni, Pd, Pt, Ru, or a combination of two or more thereof. Alternatively, the hydrogenation catalyst may comprise Co, Cu, Ni, Pd, or a combination of two or more thereof. Alternatively, the hydrogenation catalyst may comprise Co, Cu, Ni, or a combination of two or more thereof. The hydrogenation catalyst may include a support, such as alumina (Al2O3), silica (SiO2), silicon carbide (SiC), or carbon (C). Alternatively, the hydrogenation catalyst may be selected from the group consisting of Rh/C, Raney nickel, Raney copper, Raney cobalt, Ru/C, Ru/Al2O3, Pd/C, Pd/Al2O3, Pd/CaCO3, Cu/C, Cu/Al2O3, Cu/SiO2, Cu/SiC, Cu/C, a nickel catalyst on a support described above, and a combination of two or more thereof.


Alternatively, heterogeneous hydrogenation catalysts for reductive amination of the imine group of (L) the propylimine-functional organosilicon compound may include a support material on which copper, chromium, nickel, rhodium, or two or more thereof are applied as active components. Exemplary catalysts include copper at 0.3 to 15%; nickel at 0.3% to 15%, and chromium at 0.05% to 3.5%. The support material may be, for example, porous silicon dioxide or aluminium oxide. Barium may optionally be added to the support material. Chromium free hydrogenation catalysts may alternatively be used. For example a Ni/Al2O3 or Co/Al2O3 may be used, or a copper oxide/zinc oxide containing catalyst, which further comprises potassium, nickel, and/or cobalt; and additionally an alkali metal. Suitable hydrogenation catalysts are disclosed for example, in U.S. Pat. No. 7,524,997 or U.S. Pat. No. 9,567,276 and the references cited therein. Alternatively, heterogeneous hydrogenation catalysts may be commercially available, such as Rh/C catalyst, which is available from Sigma-Aldrich; Ni-5256P, which is available from BASF; and Co-179, which is also commercially available.


Other examples of suitable heterogeneous hydrogenation catalysts for use herein include Raney Nickel such as Raney Nickel 2400, Ni-3288, Raney Copper, Hysat 401 salt (Cu), ruthenium on carbon (Ru/C), rhodium on carbon (Rh/C), platinum on carbon (Pt/C), copper on silicon carbide (Cu/SiC).


Alternatively, a homogeneous hydrogenation reaction catalyst may be used herein. The homogeneous hydrogenation catalyst may be a metal complex, where the metal may be selected from the group consisting of Co, Fe, Ir, Rh, and Ru. Examples of suitable homogeneous hydrogenation catalysts are exemplified by [RhCl(PPh3)3](Wilkinson's catalyst); [Rh(NBD)(PR′3)2]+ClO4— (where R′ is an alkyl group, e.g. Et); [RuCl2(diphosphine)(1,2-diamine)](Noyori catalysts); RuCl2(TRIPHOS) (where TRIPHOS=PhP[(CH2CH2PPh2)2]; Ru(II)(dppp)(glycine) complexes (where dppp=1,3-bis(diphenylphosphino)propane); RuCl2(PPh3)3; RuCl2(CO)2(PPh3)2; IrH3(PPh3)3; [Ir(H2)(CH3COO)(PPh3)3]; cis-[Ru—Cl 2(ampy)(PP)][where ampy=2-(aminomethyl)pyridine; and PP=1,4-bis-(diphenylphosphino)butane, 1,1′-ferrocenediyl-bis(diphenylphosphine)]; Pincer RuCl(CNNR)(PP) complexes [where PP=1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,1′-ferrocenediyl-bis(diphenylphosphine); and HCNNR=4-substituted-aminomethyl-benzo[h]quinoline; R=Me, Ph]; [RuCl2(dppb)(ampy)](where dppb=1,4-Bis(diphenylphosphino)butane, ampy=2-aminomethyl pyridine); [Fe(PNPMeiPr)(CO)(H)(Br)]; [Fe(PNPMe-iPr)(H)2(CO)]; and a combination thereof.


The amount of hydrogenation catalyst used in the process depends on various factors including whether the process will be run in a batch or continuous mode, the type of propylimine-functional organosilicon compound, whether a heterogeneous or homogeneous hydrogenation catalyst is selected, and reductive amination reaction conditions such as temperature and pressure. However, when the process is run in a batch mode the amount of catalyst may be <1 weight % to 50 weight %, alternatively 5 weight % to 30 weight %, based on weight of the propylimine-functional organosilicon compound. Alternatively, the amount of catalyst may be at least 1, alternatively at least 4, alternatively at least 6.5, and alternatively at least 8, weight %; while at the same time the amount of catalyst may be up to 50, alternatively up to 20, alternatively up to 14, alternatively up to 13, alternatively up to 10, and alternatively up to 9, weight %, on the same basis. Alternatively, when the process will be run in a continuous mode, e.g., by packing a reactor with a heterogeneous hydrogenation catalyst, the amount of the heterogeneous hydrogenation catalyst may be sufficient to provide a reactor volume (filled with hydrogenation catalyst) to achieve a space time of 10 hr−1, or catalyst surface area sufficient to achieve 10 kg/hr substrate per m2 of catalyst.


(H) Hydrogen

Hydrogen is known in the art and commercially available from various sources, e.g., Air Products. Hydrogen may be used in a superstoichiometric amount with respect to the imine group of (L) the propylimine-functional organosilicon compound to permit complete reaction.


J) Solvent

A solvent, (J), that may optionally be used in the process for preparing the propylimine-functional organosilicon compound and/or the aminopropyl-functional organosilicon compound may be selected from those solvents that are neutral to the dehydrative imine generation reaction, when used in step I) described above and/or the reductive amination reaction when used in step III) of the process. The following are specific examples of such solvents: monohydric alcohols such as methanol, ethanol, and isopropyl alcohol; dioxane, ethers such as THF; aliphatic hydrocarbons, such as hexane, heptane, and paraffinic solvents; and aromatic hydrocarbons such as benzene, toluene, and xylene; and chlorinated hydrocarbons. These solvents can be used individually or in combinations of two or more. The amount of solvent is not critical and may depend on various factors such as the type and amount of each starting material to be used. For example, more solvent may be used when the propylaldehyde-functional organosilicon compound and/or the propylimine-functional organosilicon compound is resinous as opposed to oligomeric. However, the amount of solvent may be 0 to 99% based on combined weights of all starting materials used in the process.


During or after step III) of the process, removing water as described above for step II) may be performed. For example, (K) a drying agent such as an adsorbent or water complexing agent may optionally be used to remove water generated as a side product. Suitable drying agents and conditions for their use are as described above. The drying agent selected for use during or after step III) may be the same as, or different from, the drying agent selected for use during or after step I). Alternatively, if a drying agent is used during or after step I), a drying agent may be omitted during or after step III).


Step III) Reductive Amination Reaction

The reductive amination reaction in step III) can be performed using pressurized hydrogen. Hydrogen (gauge) pressure may be 10 psig (68.9 kPa) to 3000 psig (20,685 kPa), alternatively 10 psig to 2000 psig (13,790 kPa), alternatively 10 psig to 1500 psig (10,342 kPa), alternatively 200 psig (1379 kPa) to 1200 psig (8274 kPa). The reaction may be carried out at a temperature of 0 to 200° C. Alternatively, a temperature of 50 to 150° C. may be suitable for shortening the reaction time. Alternatively, the hydrogen (gauge) pressure used may be at least 25, alternatively at least 50, alternatively at least 100, alternatively at least 150, and alternatively at least 164, psig; while at the same time the hydrogen gauge pressure may be up to 800, alternatively up to 400, alternatively up to 300, alternatively up to 200, and alternatively up to 194, psig. The temperature for reaction may be at least 40, alternatively at least 50, alternatively at least 65, alternatively at least 80, ° C., while at the same time the temperature may be up to 200, alternatively up to 150, alternatively up to 120, ° C.


The reductive amination reaction can be carried out in a batch mode or a continuous mode. In a batch mode, the reductive amination reaction time depends on various factors including the amount of the catalyst and reductive amination reaction temperatures, however, step III) of the process for preparing the aminopropyl-functional organosilicon compound may be performed for 1 minute to 24 hours. Alternatively, the reductive amination reaction may be performed for at least 1 minute, alternatively at least 2 minutes, alternatively at least 1 hour, alternatively at least 2 hours, alternatively at least 3 hours, alternatively at least 3.3 hours, alternatively at least 3.7 hours, alternatively at least 4 hours, alternatively at least 4.5 hours, alternatively at least 5.5 hours, and alternatively at least 6 hours; while at the same time, the reductive amination reaction may be performed for up to 24 hours, alternatively up to 23 hours, alternatively up to 22.5 hours, alternatively up to 22 hours, alternatively up to 17.5 hours, alternatively up to 17 hours, and alternatively up to 16.5 hours.


Alternatively, in a batch mode, the terminal point of a reductive amination reaction can be considered to be the time during which the decrease in reactor pressure is no longer observed after the reaction is continued for an additional 1 to 2 hours. If reactor pressure decreases in the course of the reaction, it may be desirable to repeat the introduction of hydrogen and amine source, and to maintain it under increased pressure to shorten the reaction time. Alternatively, the reactor can be re-pressurized with hydrogen and the ammonia 1 or more times to achieve sufficient supply of hydrogen and ammonia for reaction of the imine functionality while maintaining reasonable reactor pressures.


In a continuous mode, reductive amination reaction may be performed in a trickle bed reactor. The trickle bed reactor may provide reduced capital expenditure and/or increased yield in step III) of the process, and/or easier processing for separation of the aminopropyl-functional organosilicon compound from the catalyst after step III) of the process. Alternatively, a high pressure reactor (e.g., a reactor capable of withstanding pressures up to 3000 psig (20,685 kPa), as described above, may be used for reductive amination reaction in step III) in either a batch or continuous mode.


After completion of the reductive amination reaction, (G) the hydrogenation catalyst may be separated in a pressurized inert (e.g., nitrogenous) atmosphere by any convenient means, such as filtration or adsorption, e.g., with diatomaceous earth or activated carbon, settling, centrifugation, by maintaining the hydrogenation catalyst in a structured packing or other fixed structure, or a combination thereof.


The reductive amination reaction in step III) may also produce a by-product comprising the primary amine source (as described above for use in step I)). The primary amine source may be recovered from the reductive amination reaction product produced in step III) by any convenient means, such as stripping and/or distillation. The resulting primary amine source so recovered may be recycled into the process in step I). An exemplary reaction scheme illustrating the process described above is described and shown below.


Exemplary Reaction Scheme

In an optional first step, a vinyl-functional organosilicon compound (e.g., 1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)-3-vinyltrisiloxane) is undergoes hydroformylation reaction to form a propylaldehyde-functional organosilicon compound (e.g., 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propanal). In step I), the propylaldehyde-functional organosilicon compound (e.g., 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propanal) is combined with an organic primary amine (e.g., N-butylamine) to form a propylimine-functional organosilicon compound (e.g., N-butyl-3-(1,1,1,5,5,5,-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-imine) and water as a by-product. In step II), the water may be removed, and in step III) the propylimine-functional organosilicon compound (e.g., N-butyl-3-(1,1,1,5,5,5,-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-imine) may be combined with hydrogen, ammonia, and a hydrogenation catalyst under conditions to catalyze reductive amination reaction. N-butylamine is formed as a by-product of the reductive amination reaction, and the N-butylamine can optionally be recycled back to step I). The desired product, e.g., 3-(1,1,1,5,5,5,-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-amine) also forms in step III).


Optional Step—Hydroformylation to form Aldehyde-Functional Organosilicon Compound Example



embedded image


Step I)—Dehydrative Imine Generation Reaction Example



embedded image


N-butyl-3-(1,1,1,5,5,5,-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-imine
Step II) Remove water and optionally isolate N-butyl-3-(1,1,1,5,5,5,-hexamethyl-3-((trimethylsily)oxy)trisiloxan-3-yl)propan-1-imine
Step III) Reductive Amination Reaction Example



embedded image


3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-amine
Aminopropyl-Functional Organosilicon Compound

The aminopropyl-functional organosilicon compound prepared as described above has, per molecule, at least one primary aminopropyl-functional group covalently bonded to silicon. Alternatively, the aminopropyl-functional organosilicon compound may have, per molecule, more than one primary aminopropyl-functional group covalently bonded to silicon. The primary aminopropyl-functional group, RN, may have formula:




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms, as described and exemplified above. The aminopropyl-functional organosilicon compound can have any one of the formulas above for (L) the propylimine-functional organosilicon compound, wherein at least one RI is preplaced with the group RN.


The aminopropyl-functional organosilicon compound prepared as described above may comprise (N1) an aminopropyl-functional silane of formula (N1-1): RNxSiR4(4-x), where RN, R4 and subscript x are as described above. Aminopropyl-functional silanes are exemplified by aminopropyl-functional trialkylsilanes such as (aminopropyl)-trimethylsilane and (aminopropyl)-triethylsilane.


Alternatively, the aminopropyl-functional organosilicon compound may comprise (N2) an aminopropyl-functional polyorganosiloxane. Said aminopropyl-functional polyorganosiloxane may be cyclic, linear, branched, resinous, or a combination of two or more thereof. Said aminopropyl-functional polyorganosiloxane may comprise unit formula (N2-1): (R43SiO1/2)a(R42RNSiO1/2)b(R42SiO2/2)c(R4RNSiO2/2)d(R4SiO3/2)e(RNSiO3/2)f(SiO4/2)g(ZO2)b; where each RN is an independently selected primary aminopropyl-functional group of the formula described above, and R4, Z, and subscripts a, b, c, d, e, f, g, and h are as described above for formula (B2-1).


Alternatively, (N2) the aminopropyl-functional polyorganosiloxane may comprise (N2-2) a linear polydiorganosiloxane having, per molecule, at least one primary aminopropyl-functional group; alternatively at least two primary aminopropyl-functional groups (e.g., when in the formula (N2-1) for the aminopropyl-functional polyorganosiloxane above, subscripts e=f=g=0). For example, said polydiorganosiloxane may comprise unit formula (N2-3): (R43SiO1/2)a(RNR42SiO1/2)b(R42SiO2/2)c(RIR4SiO2/2)d, where RN is as described above, and R4 and are subscripts a, b, c, and d are as described above for formula (E2-3).


Alternatively, the linear aminopropyl-functional polydiorganosiloxane of unit formula (N2-3) may be selected from the group consisting of: unit formula (N2-4): (R42RNSiO1/2)2(R42SiO2/2)m(R4RNSiO2/2)n, unit formula (N2-5): (R43SiO1/2)2(R42SiO2/2)o(R4RNSiO2/2)p, or a combination of both (N2-4) and (N2-5).


In formulae (N2-4) and (N2-5), RN is as described above, and R4 and subscripts m, n, o, and p are as described above for formulae (E2-4) and (E2-5).


The aminopropyl-functional polyorganosiloxane (N2) may comprise an aminopropyl-functional polydiorganosiloxane such as i) bis-dimethyl(aminopropyl)siloxy-terminated polydimethylsiloxane, ii) bis-dimethyl(aminopropyl)siloxy-terminated poly(dimethylsiloxane/methyl(aminopropyl)siloxane), iii) bis-dimethyl(aminopropyl)siloxy-terminated polymethyl(aminopropyl)siloxane, iv) bis-trimethylsiloxy-terminated poly(dimethylsiloxane/methyl(aminopropyl)siloxane), v) bis-trimethylsiloxy-terminated polymethyl(aminopropyl)siloxane, vi) bis-dimethyl(aminopropyl)siloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane/methyl(aminopropyl)siloxane), vii) bis-dimethyl(aminopropyl)siloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane), viii) bis-dimethyl(aminopropyl)siloxy-terminated poly(dimethylsiloxane/diphenylsiloxane), ix) bis-phenyl,methyl,(aminopropyl)-siloxy-terminated polydimethylsiloxane, and x) a combination of two or more of i) to ix).


Alternatively, (N2) the aminopropyl-functional polyorganosiloxane may be cyclic, e.g., when in unit formula (N2-1), subscripts a=b=c=e=f=g=h=0. The (N2-6) cyclic aminopropyl-functional polydiorganosiloxane may have unit formula (N2-7): (R4RNSiO2/2)a, where RN and R4 are as described above, and subscript d may be 3 to 12, alternatively 3 to 6, and alternatively 4 to 5. Examples of cyclic aminopropyl-functional polydiorganosiloxanes include 2,4,6-trimethyl-2,4,6-tri(aminopropyl)-cyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetra(aminopropyl)-cyclotetrasiloxane, 2,4,6,8,10-pentamethyl-2,4,6,8,10-penta(aminopropyl)-cyclopentasiloxane, and 2,4,6,8,10,12-hexamethyl-2,4,6,8,10,12-hexa(aminopropyl)-cyclohexasiloxane.


Alternatively, (N2-6) the cyclic aminopropyl-functional polydiorganosiloxane may have unit formula (N2-8): (R42SiO2/2)c(R4RNSiO2/2)d, where R4 and RN are as described above, subscript c is >0 to 6 and subscript d is 3 to 12. Alternatively, in formula (N2-8), a quantity (c+d) may be 3 to 12. Alternatively, in formula (N2-8), c may be 3 to 6, and d may be 3 to 6.


Alternatively, (N2) the aminopropyl-functional polyorganosiloxane may be (N2-9) oligomeric, e.g., when in unit formula (N2-1) above the quantity (a+b+c+d+e+f+g)≤50, alternatively ≤40, alternatively 30, alternatively ≤25, alternatively ≤20, alternatively ≤10, alternatively ≤5, alternatively ≤4, alternatively ≤3. The oligomer may be cyclic, linear, branched, or a combination thereof. The cyclic oligomers are as described above as formula (N2-6).


Examples of linear aminopropyl-functional polyorganosiloxane oligomers may have formula (N2-10):




embedded image


where R4 is as described above, each R2″ is independently selected from the group consisting of R4 and RN, with the proviso that at least one R2″, per molecule, is RN, and subscript z is 0 to 48. Alternatively, subscript z may be 0 to 4; alternatively 0 to 1; and alternatively 0. Alternatively, when z=0 in formula (N2-10), the aminopropyl-functional polyorganosiloxane oligomer may have formula (N2-10a):




embedded image


where R4 and RN are as described above. Examples of linear aminopropyl-functional polyorganosiloxane oligomers include 1,3-di(aminopropyl)-1,1,3,3-tetramethyldisiloxane; 1,1,1,3,3-pentamethyl-3-(aminopropyl)-disiloxane; and 1,1,1,3,5,5,5-heptamethyl-3-(aminopropyl)-trisiloxane.


Alternatively, the aminopropyl-functional polyorganosiloxane oligomer may be branched. The branched oligomer may have general formula (N2-11): RNSiR123, where RN is as described above and each R12 is selected from R13 and —OSi(R14)3; where each R13 is a monovalent hydrocarbon group; where each R14 is selected from R13, —OSi(R15)3, and —[OSiR132]iiOSiR133; where each R15 is selected from R13, —OSi(R16)3, and —[OSiR132]iiOSiR133; where each R16 is selected from R13 and —[OSiR132]iiOSiR133; and where subscript ii has a value such that 0≤ii≤100. At least two of R12 may be —OSi(R14)3. Alternatively, all three of R12 may be —OSi(R14)3.


Alternatively, in formula (L2-11) when each R12 is R13, the branched polyorganosiloxane oligomer has the following structure (N2-11a):




embedded image


where RN and R13 are as described above. Alternatively, in formula (N2-11a) each R13 may be methyl.


Alternatively, in formula (N2-11) when each R12 is —OSi(R14)3, each R14 may be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (B2-11b):




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where RN and R15 are as described above. Alternatively, each R15 may be an R13, as described above, and each R13 may be methyl.


Alternatively, in formula (N2-11), when each R12 is —OSi(R14)3, one R14 may be R13 in each —OSi(R14)3 such that each R12 is —OSiR13(R14)2. Alternatively, two R14 in —OSiR13(R14)2 may each be —OSi(R15)3 moieties such that the branched polyorganosiloxane oligomer has the following structure (N2-11c):




embedded image


where RN, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R3 may be methyl.


Alternatively, in formula (N2-11), one R12 may be R13, and two of R2 may be —OSi(R14)3. When two of R12 are —OSi(R14)3, and one R14 is R13 in each —OSi(R14)3 then two of R12 are —OSiR13(R14)2. Alternatively, each R14 in —OSiR13(R14)2 may be —OSi(R15)3 such that the branched polyorganosiloxane oligomer has the following structure (N2-11d):




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where RN, R13, and R15 are as described above. Alternatively, each R15 may be an R13, and each R13 may be methyl. Alternatively, the branched polyorganosiloxane may have 3 to 16 silicon atoms per molecule, alternatively 4 to 16 silicon atoms per molecule, and alternatively 4 to 10 silicon atoms per molecule. Examples of aminopropyl-functional branched polyorganosiloxane oligomers include 3-(3,3,3-trimethyl-112-disiloxaneyl)propan-1-amine, which has formula




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Alternatively, (N2) the aminopropyl-functional polyorganosiloxane may be branched, such as the branched oligomer described above and/or a branched aminopropyl-functional polyorganosiloxane that may have, e.g., more aminopropyl groups per molecule and/or more polymer units than the branched oligomer described above (e.g., in formula (N2-1) when the quantity (a+b+c+d+e+f+g)>50). The branched aminopropyl-functional polyorganosiloxane may have (in formula (N2-1)) a quantity (e+f+g) sufficient to provide >0 to 5 mol % of trifunctional and/or quadrifunctional units to the branched aminopropyl-functional polyorganosiloxane.


For example, the branched aminopropyl-functional polyorganosiloxane may comprise a Q branched polyorganosiloxane of unit formula (N2-13): (R43SiO1/2)q(R42RNSiO1/2)r(R42SiO2/2)s(SiO4/2)t, where RN is as described above, and R4 and subscripts q, r, s, and t are as described above for (E2-13).


Alternatively, the branched aminopropyl-functional polyorganosiloxane may comprise formula (N2-14): [RNR42Si—(O—SiR42)x—O](4-w)—Si—[O—(R42SiO)vSiR43]w, where RN is as described above, and R4 and subscripts v, w, and x are as described above with respect to formula (E2-14). Alternatively, in this formula (N2-14), each R4 is independently selected from the group consisting of methyl and phenyl.


Alternatively, the branched aminopropyl-functional polyorganosiloxane for (N2-11) may comprise a T branched polyorganosiloxane (silsesquioxane) of unit formula (N2-15): (R43SiO1/2)aa(RNR42SiO1/2)bb(R42SiO2/2)cc(RNR4SiO2/2)ee(R4SiO3/2)dd, where RN is as described above, and R4 and subscripts aa, bb, cc, dd, and ee are as described above for unit formula (E2-15).


Alternatively, (N2) the aminopropyl-functional polyorganosiloxane may comprise an aminopropyl-functional polyorganosiloxane resin, such as an aminopropyl-functional polyorganosilicate resin and/or an aminopropyl-functional silsesquioxane resin. The aminopropyl-functional polyorganosilicate resin comprises monofunctional units (“M″” units) of formula RM″3SiO1/2 and tetrafunctional silicate units (“Q” units) of formula SiO4/2, where each RM″ may be independently selected from the group consisting of R4 and RN as described above. Alternatively, each RM″ may be selected from the group consisting of an alkyl group, an aminopropyl-functional group of the formula for RN shown above, and an aryl group. Alternatively, each RM″ may be selected from methyl, (aminopropyl), (aminobutyl), and phenyl. Alternatively, at least one-third, alternatively at least two thirds of the RM″ groups are methyl groups. Alternatively, the M″ units may be exemplified by (Me3SiO1/2), (Me2PhSiO1/2), and (Me2RNSiO1/2). The polyorganosilicate resin is soluble in solvents such as those described herein as starting material (D), exemplified by liquid hydrocarbons, such as benzene, ethylbenzene, toluene, xylene, and heptane, or in liquid non-functional organosilicon compounds such as low viscosity linear and cyclic polydiorganosiloxanes.


The aminopropyl-functional polyorganosilicate resin comprises the M″ and Q units described above, and the polyorganosilicate resin further comprises units with silicon bonded hydroxyl groups, and/or hydrolyzable groups, described by moiety (ZO1/2), above, and may comprise neopentamer of formula Si(OSiRM″3)4, where RM″ is as described above, e.g., the neopentamer may be tetrakis(trimethylsiloxy)silane. 29Si NMR and 13C NMR spectroscopies may be used to measure hydroxyl and alkoxy content and molar ratio of M″ and Q units, where said ratio is expressed as {M″(resin)}/{Q(resin)}, excluding M″ and Q units from the neopentamer. M″/Q ratio represents the molar ratio of the total number of triorganosiloxy groups (M″ units) of the resinous portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. M″/Q ratio may be 0.5/1 to 1.5/1, alternatively 0.6/1 to 0.9/1.


The Mn of the aminopropyl-functional polyorganosilicate resin depends on various factors including the types of hydrocarbon groups represented by RM″ that are present. The Mn of the polyorganosilicate resin refers to the number average molecular weight measured using GPC, when the peak representing the neopentamer is excluded from the measurement. The Mn of the polyorganosilicate resin may be 1,500 Da to 30,000 Da, alternatively 1,500 Da to 15,000 Da; alternatively >3,000 Da to 8,000 Da. Alternatively, Mn of the polyorganosilicate resin may be 3,500 Da to 8,000 Da.


Alternatively, the polyorganosilicate resin may comprise unit formula (N2-17): (R43SiO1/2)mm(R42RNSiO1/2)nn(SiO4/2)oo(ZO1/2)h, where Z, R4, and RN, and subscript h are as described above and subscripts mm, nn and oo have average values such that mm≥0, nn>0, oo>0, and 0.5≤(mm+nn)/oo≤4. Alternatively, 0.6≤(mm+nn)/oo≤4; alternatively 0.7≤(mm+nn)/oo≤4, and alternatively 0.8≤(mm+nn)/oo≤4.


Alternatively, (N2) the aminopropyl-functional polyorganosiloxane may comprise (N2-18) an aminopropyl-functional silsesquioxane resin, i.e., a resin containing trifunctional (T″) units of unit formula:




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(R43SiO1/2)a(R42RNSiO1/2)b(R42SiO2/2)c(R4RNSiO2/2)d(R4SiO3/2)e(RNSiO3/2)f(ZO1/2)h; where R4 and RN are as described above, subscript f>1, 2<(e+f)<10,000; 0<(a+b)/(e+f)<3; 0<(c+d)/(e+f)<3; and 0<h/(e+f)<1.5. Alternatively, the aminopropyl-functional silsesquioxane resin may comprise unit formula (N2-19): (R4SiO3/2)e(RNSiO3/2)f(ZO1/2)h, where R4, RN, Z, and subscripts h, e and f are as described above. Alternatively, the aminopropyl-functional silsesquioxane resin may further comprise difunctional (D″) units and said aminopropyl-functional silsesquioxane resin may comprise units of formulae (R42SiO2/2)(R4RNSiO2/2)a in addition to the T units described above, i.e., a D″T″ resin, where subscripts c and d are as described above. Alternatively, the aminopropyl-functional silsesquioxane resin may further comprise monofunctional (M″) units of formulae (R43SiO1/2)a(R42RNSiO1/2)b, i.e., an M″D″T″ resin, where subscripts a and b are as described above for unit formula (E2-1).


Alternatively, (N) the aminopropyl-functional organosilicon compound may comprise unit formula (N3-1): [(R1(3-gg)RNggSi)ffNH(3-ff)]hh, where RN is as described above; each R1 is independently selected from the group consisting of an alkyl group and an aryl group as described above; each subscript ff is independently 1 or 2 as described above; subscript gg is independently 0, 1, or 2 as described above; and subscript h has a value such that 1<hh<10 as described above.


The aminopropyl-functional organosilicon compound, prepared in step III) of the process described herein may be any one of the aminopropyl-functional organosilicon compounds described above. Alternatively, the reductive amination reaction product may comprise a mixture of two or more of the aminopropyl-functional organosilicon compounds.


Alternatively, in the process described herein may be used to produce a hydrolytically unstable aminopropyl-functional organosilicon compound. The hydrolytically unstable aminopropyl-functional organosilicon compound may be, for example, any one of (N1) the aminopropyl-functional silanes and/or (N2) the aminopropyl-functional polyorganosiloxanes of any of the formulas shown above, where at least one R4 is a hydrocarbonoxy group or an acyloxy group; any (N3) aminopropyl-functional silazane; or any aminopropyl-functional polyorganosiloxane oligomer of formula (N2-10a) or (N2-11a), as described and exemplified above.


EXAMPLES

These examples are provided to illustrate the invention to one of ordinary skill in the art and should not be construed to limit the scope of the invention set forth in the claims. Starting materials used in the examples are described below in Table 1.









TABLE 1







Starting Materials









Type
Name/Chemical Description
Source





Solvent
Methanol/CH3OH
Sigma-Aldrich


Solvent
Toluene, PHR1317/C7H8
Sigma-Aldrich


Solvent
Heptane/C7H16
Sigma-Aldrich


Solvent
Isopropanol/(CH3)2CHOH
Sigma-Aldrich


Hydrogenation
Rh/C/Rhodium on carbon
Sigma-Aldrich


Catalyst


Hydrogenation
Ni-5256P catalyst/Nickel catalyst
BASF


Catalyst


Hydrogenation
Co-0179/Cobalt catalyst
BASF


Catalyst


Hydroformylation
(Acetylacetonato) dicarbonylrhodium(I)/
Commercially


Catalyst
Rh(acac)(CO)2
available


Precursor


Ligand 1
6,6′-[3,3′,5,5′-tetrakis(1,1-dimethylethyl)-1,1′-
TDCC



biphenyl]-2,2′-diyl]bis(oxy)]bis-dibenzo[d,f]



[1,3,2]dioxaphosphepin


Vinyl functional
DVTMS/1,3-divinyltetramethyldisiloxane
DSC


siloxane


Vinyl functional
MDViM, vinylmethylbis(trimethylsiloxy)silane/
DSC


siloxane
{(CH3)3SiO1/2}2



{(CH3)(CH2═CH)SiO2/2}


Vinyl functional
MviD7Mvi/3,3′-
DSC


siloxane
(1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15,17,17-



octadecamethylnonasiloxane-1,17-diyl)dipropanal


Vinyl functional
MviD328Mvi/Bis-vinyldimethylsiloxy-terminated
DSC


siloxane
polydimethylsiloxane with DP = 328


Vinyl functional
MviD558Mvi/Bis-vinyldimethylsiloxy-terminated
DSC


siloxane
polydimethylsiloxane with DP = 558


Amine Source
Ammonia/NH3
commercially




available


Primary Amine
n-butylamine/(C4H9)NH2
Sigma-Aldrich


Source


Dialdehyde-
3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-
Example 1,


siloxane A
diyl)dipropanal/C10H2203Si2
below.


MDPr-aldM
3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal/
Example 30,



C10H26O3Si3
below.


MPr-ald D7MPr-ald
Propylaldehyde terminated PDMS (DP = 7)/
Example 36,



bis(propyl-aldehyde)-terminated
below



polydimethylsiloxane, MPr-ald D7MPr-ald


MPr-ald D558MPr-ald
Propylaldehyde terminated PDMS (DP = 560)/
Example 26,



bis(propyl-aldehyde)-terminated
below.



polydimethylsiloxane, MPr-ald D558MPr-ald


MPr-ald D328MPr-ald
Propylaldehyde terminated PDMS (DP = 330)/
Example 28,



bis(propyl-aldehyde)-terminated
below.



polydimethylsiloxane, MPr-ald D328MPr-ald









In this Reference Example 1, 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal of formula




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was synthesized as follows. In a nitrogen filled glovebox, Rh(acac)(CO)2 (25.2 mg), Ligand 1(150.5 mg) and toluene (17.07 g) were added into a 30 mL glass vial with a magnetic stir bar. The mixture was stirred on a stir plate until a homogeneous solution formed. This catalyst solution was transferred to an air-tight syringe with a metal valve and subsequently removed from the glove box. In a ventilated fume hood, 1,3-divinyltetramethyldisiloxane (1000 g) was loaded to a 2 L Autoclave reactor. The reactor was sealed and loaded into the holder. The reactor was pressurized with nitrogen up to 100 psig (689.5 kPa) via the dip-tube and was carefully relieved through a valve connected to the headspace. This step was repeated three times for inertion of reactor headspace. The reactor was then pressure tested by pressurizing to 300 psig (2068.4 kPa) with nitrogen. After the pressure was released, the catalyst solution was added to the reactor via the sample loading port. The reactor was pressurized with syngas to 100 psig (689.5 kPa) and then released for three times prior to being pressurized to 80 psig (551.6 kPa) via the dip-tube. Reaction temperature was set to 50° C. until gas uptake slowed then set temp to 80° C. Agitation rate was set to 800 RPM. The intermediate cylinder containing syngas and the reactor were connected when the desired temperature was reached. The pressure was set to 100 psig (689.5 kPa). The reaction progress was monitored by a data logger which measured the pressure in the 300 mL intermediate cylinder as it supplied syngas to the reactor via a pressure reducing regulator. >98% conversion was observed after 22.5 hours. The n/i ratio was determined by 1H NMR analysis of the final product.


In this Comparative Example 2, 18 g of the 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 was loaded in a 300 mL Autoclave reactor with toluene solvent (18 g) and Ni-5256P catalyst (4.1 g). The reactor was sealed and the headspace was inerted with nitrogen. Ammonia (74.6 g, 30 equivalence) was added, and the reactor was pressurized with hydrogen to 550 psig (3792.1 kPa). The reactor was heated to 90° C. and hydrogen was added until pressure was 100 psig (689.5 kPa) higher than reactor pressure at reaction temperature. The reaction pressure was observed to be 940 psig (6481.1 kPa). Reductive amination was carried out at 90° C., 825 RPM for 4 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 17.0 g of concentrated product. The concentrated product was 59.7 wt % 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) as assayed using GC-FID.


In this Reference Example 3, a bis(propylaldehyde-terminated) polydimethylsiloxane with a DP of 560 and formula




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where subscript pp represents the average number of difunctional siloxane units per molecule and has a value of 558, was prepared as follows. In a nitrogen filled glovebox, Rh(acac)(CO)2 (90.6 mg, 0.350 mmol), Ligand 1 (550 mg, 0.656 mmol) and toluene (51.43 g, 558 mmol) were added into a 120 mL glass bottle with a magnetic stir bar. The mixture was stirred on a stir plate until a homogeneous solution formed. A portion of this solution (1.45 g) was transferred to an air-tight syringe with a metal valve and subsequently removed from the glove box. In a ventilated fume hood, Bis-dimethylvinylsiloxy-terminated polydimethylsiloxane with an average of 558 dimethylsiloxy (D) units per molecule (MVi2D558,) (195.3 g, 4.68 mmol) was loaded to a 300-mL Parr-reactor. The reactor was sealed and loaded into the holder. The reactor was pressurized with nitrogen up to 100 psi (689.5 kPa) via the dip-tube and was carefully relieved through a valve connected to the headspace for three times. The reactor was then pressure tested by pressurizing to 300 psi (2068.4 kPa) with nitrogen. After the pressure was released, the catalyst solution was added to the reactor via the sample loading port. The reactor was pressurized with syngas to 100 psi (689.5 kPa) and then released for three times prior to being pressurized 80 psi (551.6 kPa) via the dip-tube. Reaction temperature was set to 90° C. Agitation rate was set to 600 RPM. The intermediate cylinder containing syngas and the reactor were connected when the desired temperature was reached. The pressure was set to 100 psi (689.5 kPa). The reaction progress was monitored by a data logger which measured the pressure in the 300 ml intermediate cylinder as it supplied syngas to the reactor via a pressure reducing regulator. The reaction was run for four hours. The resulting product contained bis(propylaldehyde-terminated) polydimethylsiloxane with a DP of 560. The product was characterized by 1H and 29Si NMR.


In this Comparative Example 4, a bis(3-aminopropyl)-terminated poly(dimethylsiloxane) with a DP of 560 of formula:




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where subscript qq was 558 was prepared as follows. To a 2 L Autoclave reactor was loaded terminal dipropionaldehyde siloxane, (Poly[oxy(dimethylsilylene)], α-[dimethyl(3-oxopropyl)silyl]-ω-[[dimethyl(3-oxopropyl)silyl]oxy] or (C2H6OSi)1C10H22O3Si2 where n=560) prepared as described in Reference Example 3 (595 g), toluene (399 g), and 5 wt % Rh/C (36.5 g). The reactor was sealed, and the headspace was inerted with nitrogen. The mixture was agitated at 820 rpm and ammonia (44 g) was added and the mixture stirred for 18 minutes. The reactor was pressurized to 615 psig (4240.3 kPa) with hydrogen and heated to 60° C. The reactor pressure was 683 psig (4709.1 kPa). The pressure of the reactor was increased to 795 psig (5481.3 kPa) with hydrogen, and the reaction was run for 4 hours with continuous hydrogen addition. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed by rotary evaporator to collect 595.8 g of product. The product was characterized by 29Si analysis, GPC, and viscosity. The octamethylcyclotetrasiloxane content was measured by GC analysis. 29Si NMR analysis showed 78%-propyl-NH2 end capped polydimethylsiloxane.


In this Reference Example 5, 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal was prepared as follows. In a nitrogen filled glovebox, Rh(acac)(CO)2 (13.6 mg, 0.0525 mmol), Ligand 1 (84.5 mg, 0.101 mmol) and toluene (10.0 g, 108.5 mmol) were added into a 30 mL glass vial with a magnetic stir bar. The mixture was stirred on a stir plate until a homogeneous solution formed. This solution was transferred to an air-tight syringe with a metal valve and subsequently removed from the glove box. In a ventilated fume hood, vinylmethylbis(trimethylsiloxy)silane (MDviM) (1000 g, 4.02 mol) was loaded to a 2-L Autoclave-reactor. The reactor was sealed and loaded into the holder. The reactor was pressurized with nitrogen up to 100 psi (689.5 kPa) via the dip-tube and was carefully relieved through a valve connected to the headspace for three times. The reactor was then pressure tested by pressurizing to 300 psi (2068.4 kPa) with nitrogen. After the pressure was released, the catalyst solution was added to the reactor via the sample loading port. The reactor was pressurized with syngas to 100 psi (689.5 kPa) and then released for three times prior to being pressurized 80 psi (551.6 kPa) via the dip-tube. Reaction temperature was set to 75° C. Agitation rate was set to 800 RPM. The intermediate cylinder containing syngas and the reactor were connected when the desired temperature was reached. The pressure was set to 100 psi (689.5 kPa). The reaction progress was monitored by a data logger which measured the pressure in the intermediate cylinder as it supplied syngas to the reactor via a pressure reducing regulator. The resulting product contained 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal (MDPr-aldM). A portion of the crude 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal (MDPr-aldM) was purified by vacuum distillation. A vacuum distillation set-up was equipped with a 12-inch (30.48 cm) Vigreux column connected to a 500 3-neck round bottom flask equipped with a PTFE coated magnetic stir bar, an electric heating mantle controlled by a J-CHEM™ controller on the internal temperature measured with a thermoprobe and a 250 mL pre-tared collection flask. A vacuum manifold was connected to the system which included a vacuum gauge and a nitrogen line to adjust the pressure and break vacuum. Water cooling was used on the distillate condenser and a dry-ice trap was in place between the distillation system and the diaphragm vacuum pump to trap lower boiling components. A thermometer was in place to measure the temperature of the overhead vapors. A distillation was conducted by loading crude 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal (MDPr-aldM) (341.5 g) to the 500 mL reboiler. The distillation was conducted at 2 torr (266.6 Pa) pressure. A lights cut (13 g) was collected at a pot temperature of 76° C. and an overhead temperature of 66° C. The main fraction containing purified 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal (MDPr-aldM) (243 g) was collected at a pot temperature of 80-85° C. and an overhead temperature of 67-69° C. Bottoms material of 55 g was also recovered.


In this Comparative Example 6, N-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propyl)butan-1-amine was synthesized as follows. To a 300 mL Autoclave reactor was loaded 12.0 g 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal prepared as described in Reference Example 5, toluene (48.5 g), n-butylamine (3.8 g) and 5 wt % Rh/C (1.4 g). The reactor was sealed, and the headspace was inerted with nitrogen. The mixture was agitated at 800 rpm for 5 minutes. The reactor was pressurized to 463 psig (3192.3 kPa) with hydrogen and heated to 60° C. The reactor pressure was 452 psig (3116.4 kPa). The pressure of the reactor was increased to 651 psig (4488.5 kPa) with hydrogen, and the reaction was run for 4 hours with continuous hydrogen addition. The reactor was cooled and vented. The reaction product was collected, and the reactor was rinsed with toluene to collect 75.2 g of material. A portion of the material was filtered through a syringe filter, stripped of solvent, and characterized by gas chromatography and by 1H and 13C NMR analysis, which confirmed the presence of N-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propyl)butan-1-amine. GC analysis showed the N-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propyl)butan-1-amine product present in 86 area %.


In this Working Example 7, 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propan-1-amine and N-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propyl)butan-1-amine was synthesized as follows. To a 300 mL Autoclave reactor was loaded 11.7 g of 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal prepared as described in Reference Example 5, toluene (48.4 g), n-butylamine (3.9 g, 1.25 eq) and 5 wt % Rh/C (1.2 g). The reactor was sealed, and the headspace was inerted with nitrogen. To the mixture was added ammonia (18.3 g, 25 eq.), and the reactor pressure was 114 psig (786 kPa). The mixture was agitated at 800 rpm for 7 minutes. To the reactor was loaded hydrogen to 480 psig (3309.5 kPa), and the hydrogen addition was stopped. The reactor was heated to 60° C. at which point the reaction pressure was 580 psig (3999 kPa). The pressure of the reactor was increased to 798 psig (5502 kPa) with hydrogen, and the reaction was run for 4 hours with continuous hydrogen addition. The reactor was cooled and vented. The reaction product was collected, and the reactor was rinsed with toluene to collect 109.6 g of liquid. A portion of the liquid was filtered through a syringe filter, stripped of solvent, and characterized gas chromatography and by 1H and 13C NMR analysis, which showed: 67.4 GC/FID area % 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propan-1-amine 18.6 GC/FID area % N-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propyl)butan-1-amine, which combined are 86 area % products by GC.


In this Comparative Example 8, 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propan-1-amine was synthesized as follows. To a 300 mL Autoclave reactor was loaded 12.1 g of 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propanal prepared as described in Reference Example 30, toluene (48.4 g), and 5 wt % Rh/C (1.3 g). The reactor was sealed, and the headspace was inerted with nitrogen. Agitation at 800 rpm was started, and to the mixture was added ammonia (19.9 g, 26.9 eq.) and the reactor pressure was 117 psig (806.7 kPa). To the reaction was loaded hydrogen to 444 psig (3061.3 kPa), and the hydrogen addition valve closed. The reactor was heated to 60° C. at which point the reaction pressure was 610 psig (4205.8 kPa). The reactor was pressurized to 463 psig (3192.3 kPa) with hydrogen and heated to 60° C. The pressure of the reactor was increased to 816 psig (5626.1 kPa) with hydrogen, and the reaction was run for 4.5 hours with continuous hydrogen addition. The reactor was cooled and vented. The reaction product was collected to yield 60.6 g of liquid. A portion of the liquid was filtered through a syringe filter, stripped of solvent, and characterized gas chromatography and by 1H and 13C NMR and GC/FID analysis confirmed the presence of 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propan-1-amine in the reaction product. GC analysis showed 79 area % of 3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propan-1-amine product.


Working Example 7 showed improved yield using the process of the present invention, over Comparative Example 8.


In this Working Example 9, a bis(3-aminopropyl)-terminated poly(dimethylsiloxane) with a DP of 560 of formula:




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where subscript qq was 558 was prepared as follows. To a glass vessel was loaded terminal dipropionaldehyde siloxane, (Poly[oxy(dimethylsilylene)], α-[dimethyl(3-oxopropyl)silyl]-ω-[[dimethyl(3-oxopropyl)silyl]oxy] or (C2H6OSi)nC10H22O3Si2 where n=558) prepared as described in Reference Example 3 (70.0 g) and toluene (71.0 g) to form a solution. To this solution was loaded n-butylamine (0.51 g, 2.1 eq.) and mixed thoroughly. The mixture became cloudy. MgSO4 (3.0 g) was added and mixed, and the mixture was held for 16 hours. The mixture was filtered to remove MgSO4 and provide 140 g of clear liquid. The liquid was analyzed by 1H NMR to confirm the presence of the butyl imine.


To a 300 mL Autoclave reactor was loaded terminal diimine siloxane, (Poly[oxy(dimethylsilylene)], α-[dimethyl(3-(butylimino)propylsilyl]-ω-[[dimethyl(3-(butylimino)propylsilyl]oxy] or (C2H6OSi)˜ C10H40O3N2Si2 where n=558) solution prepared in this Working Example 9 (140 g) and 5 wt % Rh/C (3.5 g). The reactor was sealed, and the headspace was inerted with nitrogen. The mixture was agitated at 800 rpm and ammonia (7.1 g) was added and the mixture stirred for 13 minutes. The reactor was pressurized to 259 psig (1785.7 kPa) with hydrogen and heated to 60° C. The reactor pressure was 290 psig (1999.5 kPa). The pressure of the reactor was increased to 790 psig (5446.9 kPa) with hydrogen, and the reaction was run for 4 hours with continuous hydrogen addition. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed by rotary evaporator to collect 70.7 g of product. The product was characterized by 29Si and 1H NMR analysis. 29Si NMR analysis showed 91% primary amino-functional end capped polydimethylsiloxane.


In this Working Example 10, 50.33 g of 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 was loaded in a 300 mL Autoclave reactor with methanol (15.1 g) and Ni-5256P (6.01 g) and n-butylamine (29.7 g). The reactor was sealed and agitation was started at 400 RPM and the headspace was inerted with nitrogen. The agitation rate was increased to 800 RPM and ammonia (35.3 g, 10 equivalence) was added. The reactor was pressurized with hydrogen to 505 psig. The reactor was heated to 90° C., and hydrogen was added until pressure was 805 psig. Reductive amination was carried out at 90° C. for approximately 16 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 49.8 g of concentrated product. The concentrated product was 72.4 wt % 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) as assayed using GC-FID.


In this Working Example 11, 50.07 g of 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 was loaded in a 300 mL Autoclave reactor with methanol (15.05 g) and Ni-5256P (6.02 g) and iso-butylamine (29.72 g). The reactor was sealed and agitation was started at 400 RPM and the headspace was inerted with nitrogen. The agitation rate was increased to 820 RPM and ammonia (35.3 g, 10 equivalence) was added. The reactor was pressurized with hydrogen to 506 psig. The reactor was heated to 90° C., and hydrogen was added until pressure was 802 psig. Reductive amination was carried out at 90° C. for approximately 16 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 48.7 g of concentrated product. The concentrated product was 79.2 wt % 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) as assayed using GC-FID.


In this Working Example 12, 25.1 g of 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 was loaded in a glass vessel with methanol (25.1 g) and 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) (30.0 g) to form an imine solution. This solution was loaded to a 300 mL Autoclave reactor and Ni-5256P (2.76 g) was added. The reactor was sealed and agitation was started at 820 RPM and the headspace was inerted with nitrogen. The agitation rate was continued at 820 RPM and ammonia (37.3 g) was added. The reactor was pressurized with hydrogen to 519 psig. The reactor was heated to 90° C., and hydrogen was added until pressure was 773 psig. Reductive amination was carried out at 90° C. for approximately 16 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 48.7 g of concentrated product. The concentrated product was 79.2 wt % 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) as assayed using GC-FID.


Hydroformylation to Generate Aldehyde of Branched Organosilicon Oligomer



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In this Reference Example 13, 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propanal of formula (above) was synthesized as follows. In a nitrogen filled glovebox, Rh(acac)(CO)2 (47.5 mg), Ligand 1 (294 mg) and toluene (60.2 g) were added into a glass bottle with a magnetic stir bar. The mixture was stirred on a stir plate until a homogeneous solution formed. A portion of this catalyst solution (2.88 g) was transferred to an air-tight syringe with a metal valve and subsequently removed from the glove box. In a ventilated fume hood, 1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)-3-vinyltrisiloxane (180 g) was loaded to a 300 mL pressure reactor. The reactor was sealed. While stirring at 600 RPM, the reactor was pressurized with nitrogen up to 100 psig via the dip-tube and was carefully relieved through a valve connected to the headspace. This step was repeated three times for inertion of reactor headspace. The reactor was then pressure tested by pressurizing to 300 psig with nitrogen. After the pressure was released, the catalyst solution was added to the reactor via the sample loading port. The reactor was pressurized with syngas to 100 psig and then released for three times prior to being pressurized to 100 psig via the dip-tube. Reaction temperature was set to 80° C. The agitation rate was set to 600 RPM. The intermediate cylinder containing syngas and the reactor were connected when the desired temperature was reached. The pressure was set to 100 psig. The reaction progress was monitored by a data logger which measured the pressure in the 300 mL intermediate cylinder as it supplied syngas to the reactor via a pressure reducing regulator. >99% conversion was observed after 16 hours. n/i ratio was determined by 1H NMR analysis of the final product to be 7.5 to 1.




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In this Comparative Example 14, 40 g of 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propanal prepared as described in Example 13 was loaded in a 300 mL Autoclave reactor with THF (40.03 g) and Ni-5256P (3.99 g). The reactor was sealed, and the headspace was inerted with nitrogen. Ammonia (29.0 g, 15 equivalence) was added, and the reactor was pressurized with hydrogen to 530 psig. The reactor was heated to 100° C., and hydrogen was added until pressure was 100 psig higher than reactor pressure at reaction temperature. Reductive amination was carried out at 100° C., 920 psig, 800 RPM for 16 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 33.8 g of concentrated product. The concentrated product was 44.1 wt % 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-amine as assayed using GC-FID.




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In this Working Example 15, 30 g of 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propanal prepared as described in Example 13 was loaded to a glass round bottom flask. THF solvent (60 g) was added to form a solution. N-butylamine (6.53 g, 1.05 eq.) was added to the solution while stirring with a PTFE coated magnetic stir bar. A mild exotherm was noted. MgSO4 was added to adsorb water from the solution. The MgSO4 was removed by filtration to result in 95 g of solution containing N-butyl-3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-imine. The imine containing solution was loaded in a 300 mL Autoclave reactor with Ni-5256P catalyst (3.01 g). The reactor was sealed, and the headspace was inerted with nitrogen. Ammonia (21.7 g, 15 equivalence) was added, and the reactor was pressurized with hydrogen to 520 psig. The reactor was heated to 100° C., and hydrogen was added until pressure was 100 psig higher than reactor pressure at reaction temperature. Reductive amination was carried out at 100° C., 925 psig, 800 RPM for 20 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 25.0 g of concentrated product. The concentrated product was 75.9 wt % 3-(1,1,1,5,5,5-hexamethyl-3-((trimethylsilyl)oxy)trisiloxan-3-yl)propan-1-amine as assayed using GC-FID. This Working Example and the Comparative Example immediately preceding it show that yield dramatically increases using the process of this invention instead of attempting to form a primary amino-functional organosilicon compound directly from the corresponding aldehyde-functional organosilicon compound with ammonia.


In this Reference Example 16, T-phenyl resin propanal of formula, M0.24MPropanaldehyde0.139TPh0.62 was synthesized as follows. In a nitrogen filled glovebox, Rh(acac)(CO)2 (48.0 mg), Ligand 1(311.9 mg) and toluene (59.9 g) were combined to form a homogeneous catalyst solution. A portion of this catalyst solution (5.8 g) was transferred to an air-tight syringe with a metal valve and subsequently removed from the glove box. In a ventilated fume hood, M0.24MVi0.139TPh0.62 (90 g) dissolved in toluene (90 g) was loaded to a 300 mL pressure reactor. The reactor was sealed. While stirring at 600 RPM, the reactor was pressurized with nitrogen up to 100 psig via the dip-tube and was carefully relieved through a valve connected to the headspace. This step was repeated three times for inertion of reactor headspace. The reactor was then pressure tested by pressurizing to 300 psig with nitrogen. After the pressure was released, the catalyst solution was added to the reactor via the sample loading port. The reactor was pressurized with syngas to 100 psig and then released for three times prior to being pressurized to 100 psig via the dip-tube. Reaction temperature was set to 70° C. The agitation rate was set to 600 RPM. The intermediate cylinder containing syngas and the reactor were connected when the desired temperature was reached. The pressure was set to 100 psig. The reaction progress was monitored by a data logger which measured the pressure in the 300 mL intermediate cylinder as it supplied syngas to the reactor via a pressure reducing regulator. >99% conversion was observed after 16 hours determined by 1H NMR analysis of the final product. The toluene was removed to leave the product as a viscous liquid.


In this Working Example 17, 25.8 g of M0.24MPropanaldehyde0.14TPh0.62 as described in Example 16 was loaded to a glass round bottom flask. THF solvent (51.6 g) was added to form a solution. N-butylamine (2.55 g, 1.1 eq.) was added to the solution while stirring with a PTFE coated magnetic stir bar. MgSO4 was added to adsorb water from the solution. The MgSO4 was removed by filtration to result in a solution containing the corresponding N-butyl imine. The imine containing solution was loaded in a 300 mL Autoclave reactor with 5% Ru/C catalyst (2.6 g). The reactor was sealed, and the headspace was inerted with nitrogen. Ammonia (8.3 g, ˜15 equivalence) was added, and the reactor was pressurized with hydrogen to 530 psig. The reactor was heated to 80° C., and hydrogen was added until the pressure was 880 psig. Reductive amination was carried out at 80° C., 880 psig, 800 RPM for 18.5 hours. The reactor was cooled and vented. The reaction product was collected and filtered to remove catalyst, and the solvent was removed using a rotary evaporator to collect 27.2 g of concentrated product. The concentrated product contained M0.24MPropylamine0.139TPh0.52 as determined by 1H and 13C NMR. This Working Example 17 shows that the process of this invention can be used to make a primary amino-functional polyorganosiloxane resin.


In this Working Example 18, 299.1 g of 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 was loaded to a glass round bottom flask. Isopropanol solvent (898.1 g) was added to form a solution. Iso-butylamine (196.1 g, 2.1 eq.) was added to the solution while stirring with a mechanical stirrer. The resulting imine-functional organosilicon compound in isopropanol solution and ammonia and hydrogen were passed through a continuous tubular (trickle bed) reactor at flow rates of 0.18 mL/min, 0.036 mL/min, and 8.6 sccm, respectively. The tubular reactor internal diameter was 3 mm and contained 6.03 g of Ni-5256E catalyst. The reactor was controlled at 100° C. The effluent of the reactor was collected, and volatiles were removed under vacuum to leave a liquid. The liquid contained >50% 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) as assayed using GC-FID. This Working Example showed that the reductive amination reaction of the present invention can be practiced in a continuous mode without plugging.


In this Comparative Example 19, 300.0 g of 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 was loaded to a glass round bottom flask. Isopropanol solvent (1200 g) was added to form a solution. The resulting aldehyde-functional organosilicon compound in isopropanol solution and ammonia and hydrogen were passed through a continuous tubular (trickle bed) reactor at flow rates of 0.30 mL/min, 0.056 mL/min, and 14 sccm, respectively. The tubular reactor internal diameter was 3 mm and contained 6.0 g of Ni-5256E catalyst. The reactor was controlled at 100° C. The reactor plugged shortly after starting feed flows due the formation of a solid in the reactor and no effluent of the reactor was collected.


Working Example 18 shows the benefit of improved processability when using the process of the present invention over Comparative Example 19.


In this Prophetic Example 20, methanol (30 g) and Ni-5256P (6.0 g) are loaded to a 300 mL Autoclave reactor and the reactor is inerted with nitrogen. Ammonia (35 g, 10 equivalence) is added. The mixture is heated to 110° C. and then hydrogen is added until the pressure reaches 1000 psig. To the stirred reaction mixture (800 RPM) is pumped in 50 g of 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal prepared as described in Example 1 over a period of 60 minutes. The hydrogen is continuously fed at 1000 psig during this time. After the 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)dipropanal addition is complete the reaction is continued at 110° C. and 1000 psig for 2 hours. The reactor is cooled and vented. The reaction product is collected and filtered to remove catalyst, and the solvent is removed using a rotary evaporator to collect concentrated product.


INDUSTRIAL APPLICABILITY

When performing reductive amination of a propylaldehyde-functional organosilicon compound with ammonia, a primary imine-functional organosilicon compound is first generated, which is converted to the desired primary aminopropyl-functional organosilicon compound via reductive amination. However, primary imine groups are relatively unstable and may also cause self-condensation of the propylimine-functional organosilicon compound to form higher molecular weight by-products such as triazines and secondary amines, resulting often in significant yield loss. Furthermore, formation of these by-products often increases the viscosity of the product and/or results in the formation of solids, which makes catalyst separation difficult and limits opportunities for performing the reductive amination reaction using continuous reactor apparatus. Methods for minimizing the formation of these by-products are desired to improve yield and process robustness of a reductive amination reaction to produce aminopropyl-functional organosilicon compounds. The process described herein addresses this problem by using a primary amine source to generate a secondary propylimine-functional organosilicon compound. The secondary imine is then treated with excess ammonia, hydrogen, and a hydrogenation reaction catalyst to afford the primary aminopropyl-functional organosilicon compound and regenerate the primary amine source, which may be recycled and used in a subsequent dehydrative imine generation reaction.


In addition, during a reductive amination reaction of a propylaldehyde-functional organosilicon compound with ammonia, one molar equivalent of water per mole of aldehyde-functionality is generated as a by-product of the primary imine group formation. Certain aminopropyl-functional organosilicon compounds are hydrolytically unstable and will react with water under the conditions employed for this reductive amination reaction, and this instability results in a side reaction that can generate additional undesirable by-products. Silanes functionalized with alkoxy groups or acyloxy groups, silazanes, and branched and linear oligomeric siloxanes, such as oligomeric aminopropyl-functional siloxanes derived from branched propylaldehyde-functional siloxane oligomers (E2-10) or (E2-11) described above are more prone to side reactions in the presence of water than other aminopropyl-functional polyorganosiloxanes.


Without wishing to be bound by theory, it is thought that the ability to remove water in step II) of the process described herein (i.e., after secondary imine group and water formation via the dehydrative imine generation reaction begins in step I) and before reductive amination reaction in step III) of the process described herein can improve yield of the primary aminopropyl-functional organosilicon compound as product even when using hydrolytically unstable propylaldehyde-functional organosilicon compounds as starting materials and/or generating hydrolytically unstable propylimine-functional organosilicon compounds and hydrolytically unstable aminopropyl-functional organosilicon compounds. Furthermore, due to the improved stability of secondary imine groups over primary imine groups, the present invention provides opportunities to improve the yield and robustness of the reductive amination reaction by providing options for addressing the problems described above. Secondary imine groups are less prone to degrade via self-condensation, which in turn increases the yield of the process while also enabling alternative processing options such as the use of continuous reactors. In addition, the increased stability of the secondary imine-functional organosilicon compound intermediate allows for the water generated during the secondary imine group formation to optionally be removed using a variety of techniques including distillation or the use of a drying agent. The ability to remove the water during the early stages of the process minimizes or eliminates formation of certain by-products when using organosilicon compounds that are less hydrolytically stable in the process. Lastly, the generation of the secondary imine-functional organosilicon compound as intermediate protects the aldehyde group (of the propylaldehyde-functional organosilicon compound starting material) from oxidative decomposition.


Without wishing to be bound by theory, it is thought that the process may also provide low or no salt side product streams, shorter reaction times and/or lower cyclic siloxane by-product generation than conventional condensation reaction processes. Furthermore, the hydroformylation and reductive amination can be done in one single reactor without necessity to isolate intermediates, and may have minimal process steps.


Without wishing to be bound by theory, it is thought that another advantage of the present invention is that the aminopropyl-functional organosilicon compound produced has a high proportion of linear aminopropyl-functional groups, and that this is because propylaldehyde-functional organosilicon compounds having branched propylaldehyde moieties will react and degrade during the process described herein, such that they can be easily removed. Furthermore, the aminopropyl-functional organosilicon compound produced may have reduced cyclic siloxane (e.g., octamethylcyclotetrasiloxane, D4) content as compared to aminopropyl-functional organosilicon compounds produced via condensation chemistry using carboxylic acid catalysts or equilibration chemistry using base catalysts.


Definitions and Usage of Terms

All amounts, ratios, and percentages herein are by weight, unless otherwise indicated. The amounts of all starting materials in a composition total 100% by weight. The SUMMARY and ABSTRACT are hereby incorporated by reference. The articles ‘a’, ‘an’, and ‘the’ each refer to one or more, unless otherwise indicated by the context of specification. The singular includes the plural unless otherwise indicated. The transitional phrases “comprising”, “consisting essentially of”, and “consisting of” are used as described in the Manual of Patent Examining Procedure Ninth Edition, Revision 08.2017, Last Revised January 2018 at section § 2111.03 I., II., and III. The term “hydrolytically unstable” refers to any organosilicon compound that reacts with water at a temperature <120° C. Hydrolytically unstable organosilicon compounds herein include any organosilicon compounds used or generated, which reacts with water at a temperature <120° C. Examples include any (B) alkenyl-functional organosilicon compound, any (E) aldehyde-functional organosilicon compound, any (L) imine-functional organosilicon compound, and any primary amino-functional organosilicon compound prepared as described herein that meets one or more of the following criteria: i) one or more per molecule is acyloxy or hydrocarbonoxy; ii) the organosilicon compound is a silazane; and/or ii) any oligomeric polyorganosiloxane of formula (B2-10a), (E2-10a), (L2-10a), (N2-10a) such as 1,3-di(aminopropyl)-1,1,3,3-tetramethyldisiloxane, (B2-1a), (E2-11a), (L2-11a), or (N2-11a), such as 3-(3,3,3-trimethyl-112-disiloxaneyl)propan-1-amine, as shown above. The abbreviations used herein have the definitions in Table Z.









TABLE Z







Abbreviations








Abbreviation
Definitions





acac
acetyl acetonate


° C.
degrees Celsius


cm
centimeter


D
Difunctional siloxy unit, trimethylsiloxy unit of formula



Me2SiO2/2


DPr-ald
Difunctional siloxy unit, propylaldehyde, methylsiloxy



unit of formula (Pr-ald)(Me)SiO2/2


DP
degree of polymerization


DSC
Dow Silicones Corporation of Midland, Michigan, USA


Dvi
Difunctional siloxy unit, vinylmethylsiloxy unit



of formula (Vi)(Me)SiO2/2


Et
ethyl


FTIR
Fourier transform infra-red


g
gram


GPC
gel permeation chromatography


h
hour


kPa
kiloPascals


L
liter


M
Monofunctional siloxy unit, trimethylsiloxy unit of formula



R3SiO1/2 or Me3SiO1/2


MPr-ald
Monofunctional siloxy unit, propyladehyde, dimethylsiloxy



unit of formula (Pr-ald)(Me2)SiO1/2


Mvi
Monofunctional siloxy unit, vinyldimethylsiloxy



unit of formula (Vi)(Me2)SiO1/2


Me
methyl


mg
milligram


min
minute


mL or ml
milliliter


mm
millimeter


mmol
millimole


Mn
number average molecular weight measured by GPC


mol
mole


Mw
weight average molecular weight measured by GPC


mPa · s
milliPascal seconds


NBD
norbornadiene


NMR
nuclear magnetic resonance


Pa
Pascal


Ph
phenyl


ppm
parts per million by weight


Pr
propyl


Pr-ald
propyl-aldehyde


psi
pounds per square inch


Q
tetrafunctional siloxy unit of formula SiO4/2


RPM or rpm
revolutions per minute


RT
room temperature of 25 ± 5° C.


TDCC
The Dow Chemical Company of Midland, Michigan, USA


THF
tetrahydrofuran


μm
micrometer


Vi
vinyl









The following test methods were used herein. FTIR: The concentration of silanol groups present in the polyorganosiloxane resins (e.g., polyorganosilicate resins and/or silsesquioxane resins) was determined using FTIR spectroscopy according to ASTM Standard E-168-16. GPC: The molecular weight distribution of the polyorganosiloxanes was determined by GPC using an Agilent Technologies 1260 Infinity chromatograph and toluene as a solvent. The instrument was equipped with three columns, a PL gel 5 μm 7.5×50 mm guard column and two PLgel 5 μm Mixed-C 7.5×300 mm columns. Calibration was made using polystyrene standards. Samples were made by dissolving polyorganosiloxanes in toluene (˜1 mg/mL) and then immediately analyzing the solution by GPC (1 mL/min flow, 35° C. column temperature, 25-minute run time). 29Si NMR: Alkenyl content of starting material (B) can be measured by the technique described in “The Analytical Chemistry of Silicones” ed. A. Lee Smith, Vol. 112 in Chemical Analysis, John Wiley & Sons, Inc. (1991). Viscosity: Viscosity may be measured at 25° C. at 0.1 to 50 RPM on a Brookfield DV-II cone & plate viscometer with #CP-52 spindle, e.g., for polymers (such as certain (B2) alkenyl-functional polyorganosiloxanes and (E2) aldehyde-functional polyorganosiloxanes) with viscosity of 120 mPa·s to 250,000 mPa·s. One skilled in the art would recognize that as viscosity increases, rotation rate decreases and would be able to select appropriate spindle and rotation rate.


The aldehyde-functional organosilicon compounds, and reductive amination reaction product mixtures, in the examples above, were analyzed by 1H, 13C NMR and 29Si NMR, GC/MS,GPC and viscosity. The conversion and yield in the examples above were mainly based on 1H NMR data.


Embodiments of the Invention

In a first embodiment, a process for preparing an propylimine-functional organosilicon compound comprises:

    • I) combining, under conditions to effect a dehydrative imine generation reaction, starting materials comprising
      • (E) a propylaldehyde-functional organosilicon compound;
      • (F1) a primary amine source;
      • optionally (G) a hydrogenation catalyst;
      • optionally (J) a solvent; and
      • optionally (K) a drying agent;
      • thereby forming a dehydrative imine generation reaction product comprising (L) a propylimine-functional organosilicon compound and water;
    • optionally II) removing water; and
    • optionally isolating (L) the imine-functional organosilicon compound.


In a second embodiment a process for making an aminopropyl-functional organosilicon compound comprises: practicing the process of the first embodiment; and

    • III) combining, under conditions to catalyze reductive amination reaction, starting materials comprising
    • (L) the propylimine-functional organosilicon compound,
    • (F2) ammonia,
    • optionally (G) the hydrogenation catalyst,
    • (H) hydrogen,
    • optionally (J) the solvent, and
    • optionally (K) the drying agent,
    • with the proviso that (G) the hydrogenation catalyst is combined in at least one of step I) and step III);
    • thereby forming a reductive amination reaction product comprising the aminopropyl-functional organosilicon compound and the primary amine source.


In a third embodiment, the process of the first embodiment or the second embodiment further comprises preparing (E) the propylaldehyde-functional organosilicon compound by a hydroformylation process comprising:

    • I) combining, under conditions to catalyze hydroformylation reaction, starting materials comprising
      • (A) a gas comprising hydrogen and carbon monoxide,
      • (B) a vinyl-functional organosilicon compound, and
      • (C) a rhodium/phosphoramidite ligand complex catalyst; thereby forming a hydroformylation reaction product comprising (E) a propylaldehyde-functional organosilicon compound;
      • optionally 2) recovering (C) the rhodium/phosphoramidite ligand complex catalyst from the hydroformylation reaction product comprising (E) the propylaldehyde-functional organosilicon compound; and
    • optionally 3) isolating (E) the propylaldehyde-functional organosilicon compound.


In a fourth embodiment, in the process of any one of the first to third embodiments, the propylaldehyde-functional organosilicon compound is hydrolytically unstable, e.g., as defined above.


In a fifth embodiment, in the process of the fourth embodiment, the aldehyde-functional organosilicon compound has formula




embedded image


where each R4 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; and each RAld is an independently selected group of the formula




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms.


In a sixth embodiment, in the process of the fifth embodiment, each R4 is methyl, and RAld is linear propylaldehyde.


In a seventh embodiment, in the process of any one of the first to fourth embodiments, the propylaldehyde-functional organosilicon compound has formula




embedded image


where each R13 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; and each RAld is an independently selected group of the formula




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms.


In an eighth embodiment, in the process of the seventh embodiment, each R13 is methyl and RAld is linear propylaldehyde.


In a ninth embodiment, in the process of any one of the first to third embodiments, the propylimine-functional organosilicon compound is hydrolytically unstable, e.g., as defined above.


In a tenth embodiment, in the process of the ninth embodiment, the propylimine-functional organosilicon compound has formula




embedded image


where each R4 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; and each R1 is an independently selected group of the formula




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2, and R19 is selected from an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and an organosilicon moiety.


In an eleventh embodiment, in the process of the tenth embodiment, each R4 is methyl, G is linear, and each R19 is an alkyl group of 1 to 4 carbon atoms.


In a twelfth embodiment, in the process of the eleventh embodiment, the propylimine-functional organosilicon compound has formula




embedded image


where each R13 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; and R1 is a group of the formula




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms, and R19 is selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and an organosilicon moiety.


In a thirteenth embodiment, in the process of the twelfth embodiment, each R13 is methyl, G is linear, and each R19 is an alkyl group of 1 to 4 carbon atoms.


In a fourteenth embodiment, in the process of the second embodiment, the aminopropyl-functional organosilicon compound is hydrolytically unstable, e.g., as defined above.


In a fifteenth embodiment, in the process of the fourteenth embodiment, the aminopropyl-functional organosilicon compound has formula




embedded image


where each R4 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; each RN is an independently selected primary amino group of formula




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms.


In a sixteenth embodiment, in the process of the fifteenth embodiment, each R4 is methyl, and G is linear.


In a seventeenth embodiment, in the process of the fourteenth embodiment, the amino-functional organosilicon compound has formula




embedded image


where each R13 is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; and RN is a primary amino group of formula




embedded image


where G is a divalent hydrocarbon group free of aliphatic unsaturation that has 2 carbon atoms.


In an eighteenth embodiment, in the process of the seventeenth embodiment, each R13 is methyl, and G is linear.

Claims
  • 1. A process for preparing an amino-functional organosilicon compound from a propylimine-functional organosilicon compound, wherein the process comprises: I) combining, under conditions to effect a dehydrative imine generation reaction, starting materials comprising a propylaldehyde-functional organosilicon compound,a primary amine source,optionally a solvent, andoptionally a hydrogenation catalyst,thereby forming a reaction product comprising a propylimine-functional organosilicon compound and water;with the proviso that step I) is performed in the absence of hydrogen when the hydrogenation catalyst is present in step I);optionally II) removing water generated by the dehydrative imine generation reaction in step I); and
  • 2. The process of claim 1, wherein the propylaldehyde-functional organosilicon compound has, per molecule, at least one propylaldehyde-functional group covalently bonded to silicon, and wherein the propylaldehyde-functional group has formula propylaldehyde-functional group covalently bonded to silicon may have formula:
  • 3. The process claim 1, further comprising forming the propylaldehyde-functional organosilicon compound before step I) by a process comprising: combining, under conditions to catalyze hydroformylation reaction, starting materials comprising (A) a gas comprising hydrogen and carbon monoxide,(B) an alkenyl-functional organosilicon compound, and(C) a rhodium/ligand complex catalyst, where the ligand has formula (C1), (C2), and/or (C3),where
  • 4. The process of claim 1, further comprising recovering the propylaldehyde-functional organosilicon compound before step I).
  • 5. The process of claim 1, where the primary amine source is selected from the group consisting of: an organic primary amine of formula: R18NH2, where R18 is an alkyl group of 1 to 18 carbon atoms or an aryl group of 6 to 18 carbon atoms, anda primary amino-functional organosilicon compound.
  • 6. The process of claim 1, where the hydrogenation catalyst is a heterogeneous hydrogenation catalyst comprising a metal selected from the group consisting of Co, Cu, Fe, Ni, Ir, Pd, Pt, Rh, Ru, and a combination of two or more thereof.
  • 7. The process of claim 1, where amount of the hydrogenation catalyst is <1 weight % to 50 weight %, based on weight of the aldehyde-functional organosilicon compound.
  • 8. The process of claim 1, where in step III) one or both of conditions (i) and (ii) is satisfied, where condition (i) is that H2 pressure is 10 psig (68.9 kPa) to 1500 psig (10,342 kPa), and condition (ii) is that temperature is 0° C. to 200° C.
  • 9. The process of claim 1, further comprising pre-treating the hydrogenation catalyst before step III).
  • 10. The process of claim 1, further comprising: IV) recovering the aminopropyl-functional organosilicon compound from the reaction product during and/or after step III).
  • 11. The process of claim 1, further comprising: V) recovering the primary amine source generated in step III), and optionally recycling the primary amine source in step I).
  • 12. The process of claim 1, where step III) is performed in a continuous mode, optionally in a trickle bed reactor.
  • 13. The process of claim 1, where step II) is present, and step II) is performed before and/or during step I).
  • 14. The process of claim 13, where the propylaldehyde-functional organosilicon compound reacts with water at a temperature <120° C.
  • 15. An aminopropyl-functional organosilicon compound prepared by the process of claim 1, where the aminopropyl-functional organosilicon compound comprises an aminopropyl-functional silane of formula: RNxSiR4(4-x), where each RN is an independently selected aminopropyl-functional group of formula
  • 16. An aminopropyl-functional organosilicon compound prepared by the process of claim 1, where the aminopropyl-functional organosilicon compound comprises an amino-functional polyorganosiloxane of unit formula: (R43SiO1/2)a(R42RNSiO1/2)b(R42SiO2/2)c(R4RNSiO2/2)d(R4SiO3/2)e(RNSiO3/2)f(SiO4/2)g(ZO1/2)h; where each RN is an independently selected amino-functional group of formula
  • 17. The amino-functional organosilicon compound of claim 16, where the aminopropyl-functional polyorganosiloxane is selected from the group consisting of: a cyclic aminopropyl-functional polyorganosiloxane having a unit formula selected from the group consisting of (R4RNSiO2/2)d, where subscript d is 3 to 12; (R42SiO2/2)c(R4RNSiO2/2)d, where c is 0 to 6 and d is 3 to 12;a linear aminopropyl-functional polyorganosiloxane comprising unit formula: (R43SiO1/2)a(R42RNSiO1/2)b(R42SiO2/2)c(R4RNSiO2/2)d, where a quantity (a+b)=2, a quantity (b+d)≥1, and a quantity (a+b+c+d)≥2;an aminopropyl-functional polyorganosilicate resin comprising unit formula: (R43SiO1/2)mm(R42RNSiO1/2)nn(SiO4/2)oo(ZO1/2)h, where subscripts mm, nn, and oo represent mole percentages of each unit in the polyorganosilicate resin; and subscripts mm, nn and oo have average values such that mm≥0, nn≥0, oo≥0, and 0.5≤(mm+nn)/oo≤4;an aminopropyl-functional silsesquioxane resin comprising unit formula: (R44SiO1/2)a(R42RNSiO1/2)b(R42SiO2/2)c(R4RNSiO2/2)d(R4SiO3/2)e(RNSiO3/2)f(ZO1/2)h; where f>1, 2<(e+f)<10,000; 0<(a+b)/(e+f)<3; 0<(c+d)/(e+f)<3; and 0<h/(e+f)<1.5; anda branched aminopropyl-functional polyorganosiloxane comprising unit formula: RNSiR123, where each R12 is selected from R13 and —OSi(R14)3; where each R13 is a monovalent hydrocarbon group; where each R14 is selected from R13, —OSi(R15)3, and —[OSiR132]iiOSiR13; where each R15 is selected from R13, —OSi(R16)3, and —[OSiR132]iiOSiR13; where each R16 is selected from R13 and —[OSiR132]iiOSiR13; and where subscript ii has a value such that 0≤ii≤100, with the proviso that at least two of R12 are —OSi(R14)3.
  • 18. The aminopropyl-functional organosilicon compound of claim 17, where the aminopropyl-functional organosilicon compound has formula
  • 19. The aminopropyl-functional organosilicon compound of claim 17, where the aminopropyl-functional organosilicon compound has formula
  • 20. An aminopropyl-functional organosilicon compound prepared by the process of any one of claim 1, where the aminopropyl-functional organosilicon compound comprises an aminopropyl-functional silazane of formula: [(R1(3-gg)RNggSi)ffNH(3-ff)]hh, where each RN is an independently selected aminopropyl-functional group of formula
CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefits of U.S. Provisional Patent Application Ser. No. 63/252,639 filed on 6 Oct. 2021 and U.S. Provisional Patent Application Ser. No. 63/330,571 filed 13 Apr. 2022 under 35 U.S.C. § 119 (e). U.S. Provisional Patent Application Ser. No. 63/252,639 and U.S. Provisional Patent Application Ser. No. 63/330,571 are both hereby incorporated by reference.

PCT Information
Filing Document Filing Date Country Kind
PCT/US2022/077643 10/6/2022 WO
Provisional Applications (3)
Number Date Country
63330571 Apr 2022 US
63330571 Apr 2022 US
63252639 Oct 2021 US