Patent Application
20090264672
It is desirable to use renewable feedstocks (e.g., natural oil-derived fatty acids or fatty esters) as a source material for synthesizing industrially important organic compounds that have been conventionally manufactured from petroleum feedstocks. One useful reaction for modifying the structure of natural oil-derived feedstocks is metathesis. Metathesis is a catalytic reaction involving the rupture and reformation of carbon-carbon double bonds. When metathesis is applied directly to many natural oil-derived feedstocks, a mixture of products results. For example, when metathesis is applied to a mixture of fatty acid esters, the resulting metathesis products include a mixture of monoesters and diesters of various chain lengths. Due to the similarity in molecular weight and functionality of the products, it is difficult to separate the desired product (e.g., a particular chain length diester) from the other metathesis products.
In view of the foregoing, what is desired is a method by which bifunctional compounds such as dicarboxylic acids, dicarboxylate esters, and dicarboxylate salt compounds can be manufactured in high yields from metathesis reactions applied to starting materials such as fatty acids, fatty esters, fatty acid salts, and mixtures thereof.
The invention relates to methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds from starting compositions that are derived from renewable feedstocks, such as natural oils.
The methods of the invention make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Advantageously, the functionalized alkene intermediates can be isolated at high purity from the other cross-metathesis products and from any remaining starting material. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired bifunctional organic compound or a precursor thereto. Representative organic compounds include bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.
Accordingly, in one aspect, the invention provides a method of making diacid alkenes, diester alkenes, or dicarboxylate salt alkenes by metathesis. The method of the invention comprises the steps of:
(a) providing a starting composition comprising one or more unsaturated fatty acids, unsaturated fatty esters, or unsaturated fatty acid salts;
(b) cross-metathesizing the composition of step (a) with a short-chain olefin in the presence of a first metathesis catalyst, to form cross-metathesis products comprising: (i) one or more olefins; and (ii) one or more acid-, ester-, or carboxylate salt-functionalized alkenes;
(c) separating at least a portion of one or more of the acid-, ester-, or carboxylate salt-functionalized alkenes from the cross-metathesis products; and
(d) self-metathesizing the separated acid-, ester-, or carboxylate salt-functionalized alkene in the presence of a second metathesis catalyst to form a composition comprising one or more diacid alkenes, diester alkenes, or dicarboxylate salt alkenes.
In another aspect, the invention provides a method of making bifunctional organic compounds, the method comprising the steps of:
(a) providing a starting composition comprising one or more unsaturated fatty acids, unsaturated fatty esters, or unsaturated fatty acid salts;
(b) cross-metathesizing the starting composition of step (a) with a short-chain olefin in the presence of a first metathesis catalyst to form cross-metathesis products comprising: (i) one or more olefins; and (ii) one or more acid-, ester-, or carboxylate salt-functionalized alkenes;
(c) separating at least a portion of the one or more acid-, ester-, or carboxylate salt-functionalized alkenes from the cross-metathesis products; and
(d) cross-metathesizing the separated acid-, ester-, or carboxylate salt-functionalized alkenes with a second functionalized alkene in the presence of a metathesis catalyst to form a composition comprising a bifunctional organic compound.
As a starting composition, the method of the present invention uses unsaturated fatty acids, unsaturated fatty esters, salts of unsaturated fatty acids, or a mixture. As used herein the term “unsaturated fatty acid” refers to compounds that have an alkene chain with a terminal carboxylic acid group. The alkene chain may be a linear or branched and may optionally include one or more functional groups in addition to the carboxylic acid group. For example, some carboxylic acids include one or more hydroxyl groups. The alkene chain typically contains about 4 to about 30 carbon atoms, more typically about 4 to about 22 carbon atoms. In many embodiments, the alkene chain contains 18 carbon atoms (i.e., a C18 fatty acid). The unsaturated fatty acids have at least one carbon-carbon double bond in the alkene chain (i.e., a monounsaturated fatty acid), and may have more than one double bond (i.e., a polyunsaturated fatty acid) in the alkene chain. In exemplary embodiments, the unsaturated fatty acid has from 1 to 3 carbon-carbon double bonds in the alkene chain.
Also useful as starting compositions are unsaturated fatty esters. As used herein the term “unsaturated fatty ester” refers to a compounds that have an alkene chain with a terminal ester group. The alkene chain may be linear or branched and may optionally include one or more functional groups in addition to the ester group. For example, some unsaturated fatty esters include one or more hydroxyl groups in addition to the ester group. Unsaturated fatty esters include “unsaturated monoesters” and “unsaturated polyol esters”. Unsaturated monoesters have an alkene chain that terminates in an ester group, for example, an alkyl ester group such as a methyl ester. The alkene chain of the unsaturated monoesters typically contains about 4 to about 30 carbon atoms, more typically about 4 to 22 carbon atoms. In exemplary embodiments, the alkene chain contains 18 carbon atoms (i.e., a C18 fatty ester). The unsaturated monoesters have at least one carbon-carbon double bond in the alkene chain and may have more than one double bond in the alkene chain. In exemplary embodiments, the unsaturated fatty ester has 1 to 3 carbon-carbon double bonds in the alkene chain.
Also useful as a starting composition are metal salts of unsaturated fatty acids (i.e., carboxylate salts of unsaturated fatty acids). The metal salts may be salts of alkali metals (e.g., a group IA metal such as Li, Na, K, Rb, and Cs); alkaline earth metals (e.g., group IIA metals such as Be, Mg, Ca, Sr, and Ba); group IIIA metals (e.g., B, Al, Ga, In, and Tl); group IVA metals (e.g., Sn and Pb), group VA metals (e.g., Sb and Bi), transition metals (e.g., Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, Ru, Rh, Pd, Ag and Cd), lanthanides or actinides.
In many embodiments, the unsaturated fatty acid, ester, or carboxylate salt has a straight alkene chain and can be represented by the general formula:
CH3—(CH2)n1—[—(CH2)n3—CH═CH—]x—(CH2)n2—COOR
where:
A summary of some unsaturated fatty acids and esters is provided in TABLE A.
Unsaturated monoesters may be alkyl esters (e.g., methyl esters) or aryl esters and may be derived from unsaturated fatty acids or unsaturated glycerides by transesterifying with a monohydric alcohol. The monohydric alcohol may be any monohydric alcohol that is capable of reacting with the unsaturated free fatty acid or unsaturated glyceride to form the corresponding unsaturated monoester. In some embodiments, the monohydric alcohol is a C1 to C20 monohydric alcohol, for example, a C1 to C12 monohydric alcohol, a C1 to C8 monohydric alcohol, or a C1 to C4 monohydric alcohol. The carbon atoms of the monohydric alcohol may be arranged in a straight chain or in a branched chain structure, and may be substituted with one or more substituents. Representative examples of monohydric alcohols include methanol, ethanol, propanol (e.g., isopropanol), and butanol.
Transesterification of an unsaturated triglyceride can be represented as follows.
1 Unsaturated Triglyceride+3 Alcohol→1 Glycerol+3 Monoesters
Depending upon the make-up of the unsaturated triglyceride, the above reaction may yield one, two, or three moles of unsaturated monoester. Transesterification is typically conducted in the presence of a catalyst, for example, alkali catalysts, acid catalysts, or enzymes. Representative alkali transesterification catalysts include NaOH, KOH, sodium and potassium alkoxides (e.g., sodium methoxide), sodium ethoxide, sodium propoxide, sodium butoxide. Representative acid catalysts include sulfuric acid, phosphoric acid, hydrochloric acid, and sulfonic acids. Heterogeneous catalysts may also be used for transesterification. These include alkaline earth metals or their salts such as CaO, MgO, calcium acetate, barium acetate, natural clays, zeolites, Sn, Ge or Pb, supported on various materials such as ZnO, MgO, TiO2, activated carbon or graphite, and inorganic oxides such as alumina, silica-alumina, boria, oxides of P, Ti, Zr, Cr, Zn, Mg, Ca, and Fe. In exemplary embodiments, the triglyceride is transesterified with methanol (CH3OH) in order to form free fatty acid methyl esters.
In some embodiments, the unsaturated fatty esters are unsaturated polyol esters. As used herein the term “unsaturated polyol ester” refers to compounds that have at least one unsaturated fatty acid that is esterified to the hydroxyl group of a polyol. The other hydroxyl groups of the polyol may be unreacted, may be esterified with a saturated fatty acid, or may be esterified with an unsaturated fatty acid. The fatty acids in the polyol ester may be linear or branched and may optionally have functional groups other than the carboxylic acid such as one or more hydroxyl groups. Examples of polyols include glycerol, 1,3 propanediol, propylene glycol, erythritol, trimethylolpropane, pentaerythritol, and sorbitol. In many embodiments, unsaturated polyol esters have the general formula:
R(O—Y)m(OH)n(O—X)b
where
In many embodiments, the unsaturated polyol esters are unsaturated glycerides. As used herein the term “unsaturated glyceride” refers to a polyol ester having at least one (e.g., 1 to 3) unsaturated fatty acid that is esterified with a molecule of glycerol. The fatty acid groups may be linear or branched and may include pendant hydroxyl groups. In many embodiments, the unsaturated glycerides are represented by the general formula:
CH2A—CHB—CH2C
where
with the proviso that at least one of -A, —B, or —C is
In the above formula:
Unsaturated glycerides having two —OH groups (e.g., -A and —B are —OH) are commonly known as unsaturated monoglycerides. Unsaturated glycerides having one —OH group are commonly known as unsaturated diglycerides. Unsaturated glycerides having no —OH groups are commonly known as unsaturated triglycerides.
As shown in the formula above, the unsaturated glyceride may include monounsaturated fatty acids, polyunsaturated fatty acids, and saturated fatty acids that are esterified to the glycerol molecule. The main chain of the individual fatty acids may have the same or different chain lengths. Accordingly, the unsaturated glyceride may contain up to three different fatty acids so long as at least one fatty acid is an unsaturated fatty acid.
In many embodiments, useful starting compositions are derived from natural oils such as plant-based oils or animal fats. Representative examples of plant-based oils include canola oil, rapeseed oil, coconut oil, corn oil, cottonseed oil, olive oil, palm oil, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, linseed oil, palm kernel oil, tung oil, castor oil, and the like. Representative examples of animal fats include lard, tallow, chicken fat (yellow grease), and fish oil. Other useful oils include tall oil and algae oil.
In many embodiments, the plant-based oil is soybean oil. Soybean oil comprises unsaturated glycerides, for example, in many embodiments about 95% weight or greater (e.g., 99% weight or greater) triglycerides. Major fatty acids making up soybean oil include saturated fatty acids, for example, palmitic acid (hexadecanoic acid) and stearic acid (octadecanoic acid), and unsaturated fatty acids, for example, oleic acid (9-octadecenoic acid), linoleic acid (9,12-octadecadienoic acid), and linolenic acid (9,12,15-octadecatrienoic acid). Soybean oil is a highly unsaturated vegetable oil with many of the triglyceride molecules having at least two unsaturated fatty acids.
The method of the invention can be used to produce multiple organic acid compounds. As discussed below, the position of the carbon-carbon double bond closest to the carboxylic acid, ester, or carboxylate salt group dictates the chain length of the organic acid compound that is formed by the method of the invention.
In many embodiments, the starting composition comprises a Δ9 unsaturated fatty acid, a Δ9 unsaturated fatty ester (e.g., monoesters or polyol esters), a Δ9 unsaturated fatty acid salt, or a mixture of two or more of the foregoing. Δ9 unsaturated starting materials have a carbon-carbon double bond located between the 9th and 10th carbon atoms (i.e., between C9 and C10) in the alkene chain of the unsaturated fatty acid, ester, or salt. In determining this position, the alkene chain is numbered beginning with the carbon atom in the carbonyl group of the unsaturated fatty acid, ester, or salt. Δ9 unsaturated fatty acids, esters, and salts include polyunsaturated fatty acids, esters, or salts (i.e., having more than one carbon-carbon double bond in the alkene chain) so long as one of the carbon-carbon double bonds is located between C9 and C10. For example, included within the definition of Δ9 unsaturated fatty acids, esters, or salts are Δ9, 12 unsaturated fatty acids, esters or salts, and Δ9, 12, 15 unsaturated fatty acids, esters or salts.
In many embodiments, the Δ9 unsaturated starting materials have a straight alkene chain and may be represented by the general structure:
CH3—(CH2)n1—[—(CH2)n3—CH═CH—]x—(CH2)7—COOR
where
In exemplary embodiments, the Δ9 unsaturated starting materials have a total of 18 carbons in the alkene chain. Examples include
CH3—(CH2)7—CH═CH—(CH2)7—COOR;
CH3—(CH2)4—CH═CH—CH2—CH═CH—(CH2)7—COOR; and
CH3—CH2—CH═CH—CH2—CH═CH—CH2—CH═CH—(CH2)7—COOR.
Δ9 unsaturated fatty esters may be monoesters or polyol esters. In many embodiments, the Δ9 unsaturated polyol esters have the general structure
CH2A—CHB—CH2C
where
with the proviso that at least one of -A, —B, or —C is
In the above formula:
In exemplary embodiments, the starting composition comprises one or more C18 fatty acids, for example, oleic acid (i.e., 9-octadecenoic acid), linoleic acid (i.e., 9,12-octadecadienoic acid), and linolenic acid (i.e., 9, 12,15-octadecatrienoic acid). In other exemplary embodiments, the starting composition comprises one or more C18 fatty esters, for example, methyl oleate, methyl linoleate, and methyl linolenate. In yet another exemplary embodiment, the starting composition comprises an unsaturated glyceride comprising Δ9 fatty acids, for example, C18 Δ9 fatty acids.
Δ9 starting compositions may be derived, for example, from vegetable oils such as soybean oil, rapeseed oil, corn oil, sesame oil, cottonseed oil, sunflower oil, canola oil, safflower oil, palm oil, palm kernel oil, linseed oil, castor oil, olive oil, peanut oil, and the like. Since these vegetable oils yield predominately in glyceride form, the oils are typically processed (e.g., by transesterification) to yield unsaturated free fatty esters, unsaturated free fatty acids, or carboxylate salts thereof. Δ9 starting materials may also be derived from tung oil which typically contains oleic acid, linoleic acid, and eleostearic acid (C18; Δ9, 11, 13) in glyceride form. Δ9 starting materials may also be derived from tall oil, fish oil, lard, and tallow.
Also useful as a starting composition in the methods of the present invention are Δ5 unsaturated fatty acids, esters, or salts. As used herein “Δ5” refers to unsaturated fatty acids, esters, or salts having a carbon-carbon double bond located between the 5th and 6th carbon atom in the alkene chain of the unsaturated fatty acid, ester, or salt. In some embodiments, Δ5 unsaturated fatty acids, esters, and salts have the general structure:
CH3—(CH2)n1—[—(CH2)n3—CH═CH—]x—(CH2)3—COOR
where
The Δ5 unsaturated fatty esters may be monoesters or polyol esters (e.g., unsaturated glycerides). In many embodiments, the Δ5 unsaturated polyol esters have the general structure:
CH2A-CHB—CH2C
where
with the proviso that at least one of -A, —B, or —C is
In the above formula:
Δ5 starting compositions may be derived, for example, from meadowfoam oil which contains a twenty carbon monounsaturated fatty acid (C20:1; Δ5) in glyceride form. Δ5 starting compositions may also be derived from fish oil which typically contains eicosapentaenoic acid (C20:5; Δ5, 8, 11, 14, 17) in glyceride form.
Also useful as a starting composition in the methods of the present invention are Δ6 unsaturated fatty acids, esters, or salts. As used herein “Δ6” refers to unsaturated fatty acids, esters, or salts having a carbon-carbon double bond located between the 6th and 7th carbon atom in the alkene chain of the unsaturated fatty acid, ester, or salt. In some embodiments, Δ6 unsaturated fatty acids, esters, and salts have the general structure:
CH3—(CH2)n1—[—(CH2)n3—CH═CH—]—(CH2)4—COOR
where
The Δ6 unsaturated fatty esters may be monoesters or polyol esters (e.g., unsaturated glycerides). In many embodiments, the Δ6 unsaturated polyol esters have the general structure:
CH2A—CHB—CH2C
where
with the proviso that at least one of -A, —B, or —C is
In the above formula:
Δ6 starting compositions may be derived from coriander oil which contains an 18 carbon unsaturated fatty acid (C18:1; Δ6) in glyceride form.
Also useful as a starting composition in the methods of the present invention are Δ11 unsaturated fatty acids, esters, or salts. As used herein “Δ11” refers to unsaturated fatty acids, esters, or salts having a carbon-carbon double bond located between the 11th and 12th carbon atom in the alkene chain of the unsaturated fatty acid, ester, or salt. In some embodiments, Δ11 unsaturated fatty acids, esters, and salts have the general structure:
CH3—(CH2)n1—[—(CH2)n3—CH═CH—]x—(CH2)9—COOR
where
The Δ11 unsaturated fatty esters may be monoesters or polyol esters (e.g., unsaturated glycerides). In many embodiments, the Δ11 unsaturated polyol esters have the general structure:
CH2A-CHB—CH2C
where
with the proviso that at least one of -A, —B, or —C is
In the above formula:
Sources of Δ11 starting compositions include camelina oil which contains gondoic acid (C20:1 Δ11) at approximately 15% of the fatty acid composition.
Also useful as a starting composition in the methods of the present invention are Δ13 unsaturated fatty acids, esters, or salts. As used herein “Δ13” refers to unsaturated fatty acids, esters, or salts having a carbon-carbon double bond located between the 13th and 14th carbon atom in the alkene chain of the unsaturated fatty acid, ester, or salt. In some embodiments, Δ13 unsaturated fatty acids, esters, and salts have the general structure:
CH3—(CH2)n1—[—(CH2)n3—CH═CH—]x—(CH2)11—COOR
where
The Δ13 unsaturated fatty esters may be monoesters or polyol esters (e.g., unsaturated glycerides). In many embodiments, the Δ13 unsaturated polyol esters have the general structure
CH2A-CHB—CH2C
where
with the proviso that at least one of -A, —B, or —C is
In the above formula:
Sources of Δ13 starting compositions include crambe oil, fish oil, and high erucic acid rapeseed oil which are high in erucic acid (C22:1 Δ13) in glyceride form.
Other useful starting compositions include, for example, Δ8 and Δ4 starting materials. Δ4 starting materials may be obtained, for example, from fish oil which typically includes an amount of docosahexaenoic acid (C22:6; Δ4, 7, 10, 13, 16, 19). Δ8 starting materials may also be obtained from fish oil which typically includes an amount of eicosatetraenoic acid (C20:4; Δ8, 11, 14, 17).
A summary of some useful starting compositions is provided in TABLE B.
According to the method of the invention, the starting composition is cross-metathesized with a short-chain olefin in the presence of a metathesis catalyst to form cross-metathesis products comprising: (i) one or more olefin compounds; and (ii) one or more acid-, ester-, or carboxylate salt-functionalized alkenes having at least one carbon-carbon double bond.
Short-chain olefins are short chain length organic compounds that have at least one carbon-carbon double bond. In many embodiments, the short chain olefins have between about 4 and about 9 carbon atoms. Short chain olefins can be represented by the structure (II):
R7R8C═CR9R10 (II)
The organic group may be an aliphatic group, an alicyclic group, or an aromatic group. Organic groups may optionally include heteroatoms (e.g., O, N, or S atoms), as well as functional groups (e.g., carbonyl groups). The term aliphatic group means a saturated or unsaturated, linear or branched, hydrocarbon group. This term is used to encompass alkyl groups. The term alkyl group means a monovalent, saturated, linear, branched, or cyclic hydrocarbon group. Representative examples of alkyl groups include methyl, ethyl, propyl (n-propyl or i-propyl), butyl (n-butyl or t-butyl), pentyl, hexyl, and heptyl. An alicyclic group is an aliphatic group arranged in one or more closed ring structures. The term is used to encompass saturated (i.e., cycloparaffins) or unsaturated (cycloolefins or cycloacetylenes) groups. An aromatic or aryl group is an unsaturated cyclic hydrocarbon having a conjugated ring structure. Included within aromatic or aryl groups are those possessing both an aromatic ring structure and an aliphatic or alicyclic group.
In many embodiments, the short-chain olefin is a short-chain internal olefin. Short-chain internal olefins may be represented by structure (II):
R7R8C═CR9R10 (II)
Short-chain internal olefins may be symmetric or asymmetric. Symmetric short-chain internal olefins having one carbon-carbon double bond may be represented by structure (II-A):
R7CH═CHR9 (II-A)
Representative examples of symmetric short-chain internal olefins include 2-butene, 3-hexene, and 4-octene. In some embodiments, the short-chain internal olefin is asymmetric. Representative examples of asymmetric short-chain internal olefins include 2-pentene, 2-hexene, 2-heptene, 3-heptene, 2-octene, 3-octene, 2-nonene, 3-nonene, and 4-nonene.
In many embodiments, symmetric short-chain internal olefins are preferred for cross-metathesis because the cross-metathesis products that result will include fewer products than if an asymmetric short-chain internal olefin is used for cross-metathesis. For example, as shown below, when a first double-bond containing compound (i.e., A=B) is cross-metathesized with a symmetric short-chain internal olefin (i.e., represented by C═C), two cross-metathesis products are produced. By contrast, when the same double-bond containing compound is cross-metathesized with an asymmetric short-chain internal olefin (i.e., represented by C=D), four cross-metathesis products are produced.
Metathesis of Symmetric Short-chain Internal Olefin (C═C)
A=B+C═CA=C+B═C
Metathesis of Asymmetric Short-chain Internal Olefin (C=D):
A=B+C=DA=C+B═C+A=D+B=D
In some embodiments, the short-chain olefin is an α-olefin. Alpha olefins are included in general structure (II) when R7, R8, and R9 are all hydrogen. Representative α-olefin are shown in general structure (II-B):
CH2═CH—R10 (II-B)
Representative —R10 groups include —(CH2)n—CH3, where n ranges from 0 to 6. Exemplary alpha olefin compounds include 1-propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, and 1-nonene.
Metathesis reactions proceed in the presence of a catalytically effective amount of a metathesis catalyst. The term “metathesis catalyst” includes any catalyst or catalyst system which catalyzes the olefin metathesis reaction.
Any known or future-developed metathesis catalyst may be used, alone or in combination with one or more additional catalysts, in accordance with embodiments of the present method. Exemplary metathesis catalysts include metal carbene catalysts based upon transition metals, for example, ruthenium, molybdenum, osmium, chromium, rhenium, and tungsten. In certain embodiments, the metathesis catalyst is preferably a Group 8 transition metal complex having the structure of formula (III)
in which the various substituents are as follows:
wherein any two or more of X>, X2, L1, L2, L3, R1, and R2 can be taken together to form a cyclic group, and further wherein any one or more of X1, X2, L1, L2, L3, R1, and R2 may be attached to a support.
Preferred catalysts contain Ru or Os as the Group 8 transition metal, with Ru particularly preferred.
Numerous embodiments of the catalysts useful in the reactions of the disclosure are described in more detail infra. For the sake of convenience, the catalysts are described in groups, but it should be emphasized that these groups are not meant to be limiting in any way. That is, any of the catalysts useful in the disclosure may fit the description of more than one of the groups described herein.
A first group of catalysts, then, are commonly referred to as 1st Generation Grubbs-type catalysts, and have the structure of formula (III). For the first group of catalysts, M and m are as described above, and n, X1, X2, L1, L2, L3, R1, and R2 are described as follows.
For the first group of catalysts, n is 0, and L1 and L2 are independently selected from phosphine, sulfonated phosphine, phosphite, phosphinite, phosphonite, arsine, stibine, ether, amine, amide, imine, sulfoxide, carboxyl, nitrosyl, pyridine, substituted pyridine, imidazole, substituted imidazole, pyrazine, and thioether. Exemplary ligands are trisubstituted phosphines.
X1 and X2 are anionic ligands, and may be the same or different, or are linked together to form a cyclic group, typically although not necessarily a five- to eight-membered ring. In preferred embodiments, X1 and X2 are each independently hydrogen, halide, or one of the following groups: C1-C20 alkyl, C5-C24 aryl, C1-C20 alkoxy, C5-C24 aryloxy, C2-C20 alkoxycarbonyl, C6-C24 aryloxycarbonyl, C2-C24 acyl, C2-C24 acyloxy, C1-C20 alkylsulfonato, C5-C24 arylsulfonato, C1-C20 alkylsulfanyl, C5-C24 arylsulfanyl, C1-C20 alkylsulfinyl, or C5-C24 arylsulfinyl. Optionally, X1 and X2 may be substituted with one or more moieties selected from C1-C12 alkyl, C1-C12 alkoxy, C5-C24 aryl, and halide, which may, in turn, with the exception of halide, be further substituted with one or more groups selected from halide, C1-C6 alkyl, C1-C6 alkoxy, and phenyl. In more preferred embodiments, X1 and X2 are halide, benzoate, C2-C6 acyl, C2-C6 alkoxycarbonyl, C1-C6 alkyl, phenoxy, C1-C6 alkoxy, C1-C6 alkylsulfanyl, aryl, or C1-C6 alkylsulfonyl. In even more preferred embodiments, X1 and X2 are each halide, CF3CO2, CH3CO2, CFH2CO2, (CH3)3CO, (CF3)2(CH3)CO, (CF3)(CH3)2CO, PhO, MeO, EtO, tosylate, mesylate, or trifluoromethane-sulfonate. In the most preferred embodiments, X1 and X2 are each chloride.
R1 and R2 are independently selected from hydrogen, hydrocarbyl (e.g., C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C6-C24 alkaryl, C6-C24 aralkyl, etc.), substituted hydrocarbyl (e.g., substituted C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C6-C24 alkaryl, C6-C24 aralkyl, etc.), heteroatom-containing hydrocarbyl (e.g., heteroatom-containing C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C6-C24 alkaryl, C6-C24 aralkyl, etc.), and substituted heteroatom-containing hydrocarbyl (e.g., substituted heteroatom-containing C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C6-C24 alkaryl, C6-C24 aralkyl, etc.), and functional groups. R1 and R2 may also be linked to form a cyclic group, which may be aliphatic or aromatic, and may contain substituents and/or heteroatoms. Generally, such a cyclic group will contain 4 to 12, preferably 5, 6, 7, or 8 ring atoms.
In preferred catalysts, R1 is hydrogen and R2 is selected from C1-C20 alkyl, C2-C20 alkenyl, and C5-C24 aryl, more preferably C1-C6 alkyl, C2-C6 alkenyl, and C5-C14 aryl. Still more preferably, R2 is phenyl, vinyl, methyl, isopropyl, or t-butyl, optionally substituted with one or more moieties selected from C1-C6 alkyl, C1-C6 alkoxy, phenyl, and a functional group Fn as defined earlier herein. Most preferably, R2 is phenyl or vinyl substituted with one or more moieties selected from methyl, ethyl, chloro, bromo, iodo, fluoro, nitro, dimethylamino, methyl, methoxy, and phenyl. Optimally, R2 is phenyl or —C═C(CH3)2.
Any two or more (typically two, three, or four) of X1, X2, L1, L2, L3, R1, and R2 can be taken together to form a cyclic group, as disclosed, for example, in U.S. Pat. No. 5,312,940 to Grubbs et al. When any of X1, X2, L1, L2, L3, R1, and R2 are linked to form cyclic groups, those cyclic groups may contain 4 to 12, preferably 4, 5, 6, 7 or 8 atoms, or may comprise two or three of such rings, which may be either fused or linked. The cyclic groups may be aliphatic or aromatic, and may be heteroatom-containing and/or substituted. The cyclic group may, in some cases, form a bidentate ligand or a tridentate ligand. Examples of bidentate ligands include, but are not limited to, bisphosphines, dialkoxides, alkyldiketonates, and aryldiketonates.
A second group of catalysts, commonly referred to as 2nd Generation Grubbs-type catalysts, have the structure of formula (III), wherein L1 is a carbene ligand having the structure of formula (IV)
such that the complex may have the structure of formula (V)
wherein M, m, n, X1, X2, L2, L3, R1, and R2 are as defined for the first group of catalysts, and the remaining substituents are as follows.
X and Y are heteroatoms typically selected from N, O, S, and P. Since O and S are divalent, p is necessarily zero when X is O or S, and q is necessarily zero when Y is O or S. However, when X is N or P, then p is 1, and when Y is N or P, then q is 1. In a preferred embodiment, both X and Y are N.
Q1, Q2, Q3, and Q4 are linkers, e.g., hydrocarbylene (including substituted hydrocarbylene, heteroatom-containing hydrocarbylene, and substituted heteroatom-containing hydrocarbylene, such as substituted and/or heteroatom-containing alkylene) or —(CO)—, and w, x, y, and z are independently zero or 1, meaning that each linker is optional. Preferably, w, x, y, and z are all zero. Further, two or more substituents on adjacent atoms within Q1, Q2, Q3, and Q4 may be linked to form an additional cyclic group.
R3, R3A, R4, and R4A are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-contain ing hydrocarbyl.
In addition, any two or more of X1, X2, L1, L2, L3, R1, R2, R3, R3A, R4, and R4A can be taken together to form a cyclic group, and any one or more of X1, X2, L1, L2, L3, R1, R2, R3, R3A, R4, and R4A may be attached to a support.
Preferably, R3A and R4A are linked to form a cyclic group so that the carbene ligand is an heterocyclic carbene and preferably an N-heterocyclic carbene, such as the N-heterocylic carbene having the structure of formula (VI):
where R3 and R4 are defined above, with preferably at least one of R3 and R4, and more preferably both R3 and R4, being alicyclic or aromatic of one to about five rings, and optionally containing one or more heteroatoms and/or substituents. Q is a linker, typically a hydrocarbylene linker, including substituted hydrocarbylene, heteroatom-containing hydrocarbylene, and substituted heteroatom-containing hydrocarbylene linkers, wherein two or more substituents on adjacent atoms within Q may also be linked to form an additional cyclic structure, which may be similarly substituted to provide a fused polycyclic structure of two to about five cyclic groups. Q is often, although again not necessarily, a two-atom linkage or a three-atom linkage.
Examples of N-heterocyclic carbene ligands suitable as L1 thus include, but are not limited to, the following:
When M is ruthenium, then, the preferred complexes have the structure of formula (VII).
In a more preferred embodiment, Q is a two-atom linkage having the structure —CR11R12CR13R14— or —CR11═CR13—, preferably —CR11R12—CR13R14—, wherein R11, R12, R13, and R14 are independently selected from hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups. Examples of functional groups here include carboxyl, C1-C20 alkoxy, C5-C24 aryloxy, C2-C20 alkoxycarbonyl, C5-C24 alkoxycarbonyl, C2-C24 acyloxy, C1-C20 alkylthio, C5-C24 arylthio, C1-C20 alkylsulfonyl, and C1-C20 alkylsulfinyl, optionally substituted with one or more moieties selected from C1-C12 alkyl, C1-C12 alkoxy, C5-C14 aryl, hydroxyl, sulfhydryl, formyl, and halide. R11, R12, R13, and R14 are preferably independently selected from hydrogen, C1-C12 alkyl, substituted C1-C12 alkyl, C1-C12 heteroalkyl, substituted C1-C12 heteroalkyl, phenyl, and substituted phenyl. Alternatively, any two of R11, R12, R13, and R14 may be linked together to form a substituted or unsubstituted, saturated or unsaturated ring structure, e.g., a C4-C12 alicyclic group or a C5 or C6 aryl group, which may itself be substituted, e.g., with linked or fused alicyclic or aromatic groups, or with other substituents.
When R3 and R4 are aromatic, they are typically although not necessarily composed of one or two aromatic rings, which may or may not be substituted, e.g., R3 and R4 may be phenyl, substituted phenyl, biphenyl, substituted biphenyl, or the like. In one preferred embodiment, R3 and R4 are the same and are each unsubstituted phenyl or phenyl substituted with up to three substituents selected from C1-C20 alkyl, substituted C1-C20 alkyl, C1-C20 heteroalkyl, substituted C1-C20 heteroalkyl, C5-C24 aryl, substituted C5-C24 aryl, C5-C24 heteroaryl, C6-C24 aralkyl, C6-C24 alkaryl, or halide. Preferably, any substituents present are hydrogen, C1-C12 alkyl, C1-C12 alkoxy, C5-C14 aryl, substituted C5-C14 aryl, or halide. As an example, R3 and R4 are mesityl.
In a third group of catalysts having the structure of formula (III), M, m, n, X1, X2, R1, and R2 are as defined for the first group of catalysts, L1 is a strongly coordinating neutral electron donor ligand such as any of those described for the first and second groups of catalysts, and L2 and L3 are weakly coordinating neutral electron donor ligands in the form of optionally substituted heterocyclic groups. Again, n is zero or 1, such that L3 may or may not be present. Generally, in the third group of catalysts, L2 and L3 are optionally substituted five- or six-membered monocyclic groups containing 1 to 4, preferably 1 to 3, most preferably 1 to 2 heteroatoms, or are optionally substituted bicyclic or polycyclic structures composed of 2 to 5 such five- or six-membered monocyclic groups. If the heterocyclic group is substituted, it should not be substituted on a coordinating heteroatom, and any one cyclic moiety within a heterocyclic group will generally not be substituted with more than 3 substituents.
For the third group of catalysts, examples of L2 and L3 include, without limitation, heterocycles containing nitrogen, sulfur, oxygen, or a mixture thereof.
Examples of nitrogen-containing heterocycles appropriate for L2 and L3 include pyridine, bipyridine, pyridazine, pyrimidine, bipyridamine, pyrazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, pyrrole, 2H-pyrrole, 3H-pyrrole, pyrazole, 2H-imidazole, 1,2,3-triazole, 1,2,4-triazole, indole, 3H-indole, 1H-isoindole, cyclopenta(b)pyridine, indazole, quinoline, bisquinoline, isoquinoline, bisisoquinoline, cinnoline, quinazoline, naphthyridine, piperidine, piperazine, pyrrolidine, pyrazolidine, quinuclidine, imidazolidine, picolylimine, purine, benzimidazole, bisimidazole, phenazine, acridine, and carbazole.
Examples of sulfur-containing heterocycles appropriate for L2 and L3 include thiophene, 1,2-dithiole, 1,3-dithiole, thiepin, benzo(b)thiophene, benzo(c)thiophene, thionaphthene, dibenzothiophene, 2H-thiopyran, 4H-thiopyran, and thioanthrene.
Examples of oxygen-containing heterocycles appropriate for L2 and L3 include 2H-pyran, 4H-pyran, 2-pyrone, 4-pyrone, 1,2-dioxin, 1,3-dioxin, oxepin, furan, 2H-1-benzopyran, coumarin, coumarone, chromene, chroman-4-one, isochromen-1-one, isochromen-3-one, xanthene, tetrahydrofuran, 1,4-dioxan, and dibenzofuran.
Examples of mixed heterocycles appropriate for L2 and L3 include isoxazole, oxazole, thiazole, isothiazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,3,4-oxadiazole, 1,2,3,4-oxatriazole, 1,2,3,5-oxatriazole, 3H-1,2,3-dioxazole, 3H-1,2-oxathiole, 1,3-oxathiole, 4H-1,2-oxazine, 2H-1,3-oxazine, 1,4-oxazine, 1,2,5-oxathiazine, o-isooxazine, phenoxazine, phenothiazine, pyrano[3,4-b]pyrrole, indoxazine, benzoxazole, anthranil, and morpholine.
Preferred L2 and L3 ligands are aromatic nitrogen-containing and oxygen-containing heterocycles, and particularly preferred L2 and L3 ligands are monocyclic N-heteroaryl ligands that are optionally substituted with 1 to 3, preferably 1 or 2, substituents. Specific examples of particularly preferred L2 and L3 ligands are pyridine and substituted pyridines, such as 3-bromopyridine, 4-bromopyridine, 3,5-dibromopyridine, 2,4,6-tribromopyridine, 2,6-dibromopyridine, 3-chloropyridine, 4-chloropyridine, 3,5-dichloropyridine, 2,4,6-trichloropyridine, 2,6-dichloropyridine, 4-iodopyridine, 3,5-diiodopyridine, 3,5-dibromo-4-methylpyridine, 3,5-dichloro-4-methylpyridine, 3,5-dimethyl-4-bromopyridine, 3,5-dimethylpyridine, 4-methylpyridine, 3,5-diisopropylpyridine, 2,4,6-trimethylpyridine, 2,4,6-triisopropylpyridine, 4-(tert-butyl)pyridine, 4-phenylpyridine, 3,5-diphenylpyridine, 3,5-dichloro-4-phenylpyridine, and the like.
In general, any substituents present on L2 and/or L3 are selected from halo, C1-C20 alkyl, substituted C1-C20 alkyl, C1-C20 heteroalkyl, substituted C1-C20 heteroalkyl, C5-C24 aryl, substituted C5-C24 aryl, C5-C24 heteroaryl, substituted C5-C24 heteroaryl, C6-C24 alkaryl, substituted C6-C24 alkaryl, C6-C24 heteroalkaryl, substituted C6-C24 heteroalkaryl, C6-C24 aralkyl, substituted C6-C24 aralkyl, C6-C24 heteroaralkyl, substituted C6-C24 heteroaralkyl, and functional groups, with suitable functional groups including, without limitation, C1-C20 alkoxy, C5-C24 aryloxy, C2-C20 alkylcarbonyl, C6-C24 arylcarbonyl, C2-C20 alkylcarbonyloxy, C6-C24 arylcarbonyloxy, C2-C20 alkoxycarbonyl, C6-C24 aryloxycarbonyl, halocarbonyl, C2-C20 alkylcarbonato, C6-C24 arylcarbonato, carboxy, carboxylato, carbamoyl, mono-(C1-C20 alkyl)-substituted carbamoyl, di-(C1-C20 alkyl)- substituted carbamoyl, di-N—(C1-C20 alkyl), N—(C5-C24 aryl)-substituted carbamoyl, mono-(C5-C24 aryl)-substituted carbamoyl, di-(C6-C24 aryl)-substituted carbamoyl, thiocarbamoyl, mono-(C1-C20 alkyl)-substituted thiocarbamoyl, di-(C1-C20 alkyl)-substituted thiocarbamoyl, di-N—(C1-C20 alkyl)-N—(C6-C24 aryl)-substituted thiocarbamoyl, mono-(C6-C24 aryl)-substituted thiocarbamoyl, di-(C6-C24 aryl)-substituted thiocarbamoyl, carbamido, formyl, thioformyl, amino, mono-(C1-C20 alkyl)-substituted amino, di-(C1-C20 alkyl)-substituted amino, mono-(C5-C24 aryl)-substituted amino, di-(C5-C24 aryl)-substituted amino, di-N—(C1-C20 alkyl)—N—(C5-C24 aryl)-substituted amino, C2-C20 alkylamido, C6-C24 arylamido, imino, C1-C20 alkylimino, C5-C24arylimino, nitro, and nitroso. In addition, two adjacent substituents may be taken together to form a ring, generally a five- or six-membered alicyclic or aryl ring, optionally containing 1 to 3 heteroatoms and 1 to 3 substituents as above.
Preferred substituents on L2 and L3 include, without limitation, halo, C1-C12 alkyl, substituted C1-C12 alkyl, C1-C12 heteroalkyl, substituted C1-C12 heteroalkyl, C5-C14 aryl, substituted C5-C14 aryl, C5-C14 heteroaryl, substituted C5-C14 heteroaryl, C6-C16 alkaryl, substituted C6-C16 alkaryl, C6-C16 heteroalkaryl, substituted C6-C16 heteroalkaryl, C6-C16 aralkyl, substituted C6-C16 aralkyl, C6-C16 heteroaralkyl, substituted C6-C16 heteroaralkyl, C1-C12 alkoxy, C5-C14 aryloxy, C2-C12 alkylcarbonyl, C6-C14 arylcarbonyl, C2-C12 alkylcarbonyloxy, C6-C14 arylcarbonyloxy, C2-C12 alkoxycarbonyl, C6-C14 aryloxycarbonyl, halocarbonyl, formyl, amino, mono-(C1-C12alkyl)-substituted amino, di-(C1-C12alkyl)-substituted amino, mono-(C5-C14 aryl)-substituted amino, di-(C5-C14 aryl)-substituted amino, and nitro.
Of the foregoing, the most preferred substituents are halo, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, phenyl, substituted phenyl, formyl, N,N-diC1-C6 alkyl)amino, nitro, and nitrogen heterocycles as described above (including, for example, pyrrolidine, piperidine, piperazine, pyrazine, pyrimidine, pyridine, pyridazine, etc.).
L2 and L3 may also be taken together to form a bidentate or multidentate ligand containing two or more, generally two, coordinating heteroatoms such as N, O, S, or P, with preferred such ligands being diimine ligands of the Brookhart type. One representative bidentate ligand has the structure of formula (VIII)
wherein R15, R16, R17, and R18 hydrocarbyl (e.g., C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C6-C24 alkaryl, or C6-C24 aralkyl), substituted hydrocarbyl (e.g., substituted C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C6-C24 alkaryl, or C6-C24 aralkyl), heteroatom-containing hydrocarbyl (e.g., C1-C20 heteroalkyl, C5-C24 heteroaryl, heteroatom-containing C6-C24 aralkyl, or heteroatom-containing C6-C24 alkaryl), or substituted heteroatom-containing hydrocarbyl (e.g., substituted C1-C20 heteroalkyl, C5-C24 heteroaryl, heteroatom-containing C6-C24 aralkyl, or heteroatom-containing C6-C24 alkaryl), or (1) R15 and R16, (2) R17 and R18, (3) R16 and R17, or (4) both R15 and R16, and R17 and R18, may be taken together to form a ring, i.e., an N-heterocycle. Preferred cyclic groups in such a case are five- and six-membered rings, typically aromatic rings.
In a fourth group of catalysts that have the structure of formula (III), two of the substituents are taken together to form a bidentate ligand or a tridentate ligand. Examples of bidentate ligands include, but are not limited to, bisphosphines, dialkoxides, alkyldiketonates, and aryldiketonates. Specific examples include —P(Ph)2CH2CH2P(Ph)2—, —As(Ph)2CH2CH2As(Ph2)—, —P(Ph)2CH2CH2C(CF3)2O—, binaphtholate dianions, pinacolate dianions, —P(CH3)2(CH2)2P(CH3)2—, and —OC(CH3)2(CH3)2CO—. Preferred bidentate ligands are —P(Ph)2 CH2CH2P(Ph)2— and —P(CH3)2(CH2)2P(CH3)2—. Tridentate ligands include, but are not limited to, (CH3)2 NCH2CH2P(Ph)CH2CH2N(CH3)2. Other preferred tridentate ligands are those in which any three of X1, X2, L1, L2, L3, R1, and R2 (e.g., X1, L1, and L2) are taken together to be cyclopentadienyl, indenyl, or fluorenyl, each optionally substituted with C2-C20 alkenyl, C2-C20 alkynyl, C1-C20 alkyl, C5-C20 aryl, C1-C20 alkoxy, C2-C20 alkenyloxy, C2-C20 alkynyloxy, C5-C20 aryloxy, C2-C20 alkoxycarbonyl, C1-C20 alkylthio, C1-C20 alkylsulfonyl, or C1-C20 alkylsulfinyl, each of which may be further substituted with C1-C6 alkyl, halide, C1-C6 alkoxy or with a phenyl group optionally substituted with halide, C1-C6 alkyl, or C1-C6 alkoxy. More preferably, in compounds of this type, X, L1, and L2 are taken together to be cyclopentadienyl or indenyl, each optionally substituted with vinyl, C1-C10 alkyl, C5-C20 aryl, C1-C10 carboxylate, C2-C10 alkoxycarbonyl, C1-C10 alkoxy, or C5-C20 aryloxy, each optionally substituted with C1-C6 alkyl, halide, C1-C6 alkoxy or with a phenyl group optionally substituted with halide, C1-C6 alkyl or C1-C6 alkoxy. Most preferably, X, L1 and L2 may be taken together to be cyclopentadienyl, optionally substituted with vinyl, hydrogen, methyl, or phenyl. Tetradentate ligands include, but are not limited to O2C(CH2)2P(Ph)(CH2)2P(Ph)(CH2)2CO2, phthalocyanines, and porphyrins.
Complexes wherein L2 and R2 are linked are examples of the fourth group of catalysts, and are commonly called “Grubbs-Hoveyda” catalysts. Examples of Grubbs-Hoveyda-type catalysts include the following:
wherein L1, X1, X2, and M are as described for any of the other groups of catalysts.
In addition to the catalysts that have the structure of formula (III), as described above, other transition metal carbene complexes include, but are not limited to:
neutral ruthenium or osmium metal carbene complexes containing metal centers that are formally in the +2 oxidation state, have an electron count of 16, are penta-coordinated, and are of the general formula (IX);
neutral ruthenium or osmium metal carbene complexes containing metal centers that are formally in the +2 oxidation state, have an electron count of 18, are hexa-coordinated, and are of the general formula (X);
cationic ruthenium or osmium metal carbene complexes containing metal centers that are formally in the +2 oxidation state, have an electron count of 14, are tetra-coordinated, and are of the general formula (XI); and
cationic ruthenium or osmium metal carbene complexes containing metal centers that are formally in the +2 oxidation state, have an electron count of 14, are tetra-coordinated, and are of the general formula (XII)
wherein: X1, X2, L1, L2, n, L3, R1, and R2 are as defined for any of the previously defined four groups of catalysts; r and s are independently zero or 1; t is an integer in the range of zero to 5;
Y is any non-coordinating anion (e.g., a halide ion, BF4−, etc.); Z1 and Z2 are independently selected from —O—, —S—, —NR2—, —PR2—, —P(═O)R2—, —P(OR2)—, —P(═O)(OR2)—, —C(═O)—, —C(═O)O—, —OC(═O)—, —OC(═O)O—, —S(═O)—, and —S(═O)2—; Z3 is any cationic moiety such as —P(R2)3+ or —N(R2)3+; and
any two or more of X1, X2, L1, L2, L3, n, Z1, Z2, Z3, R1, and R2 may be taken together to form a cyclic group, e.g., a multidentate ligand, and
wherein any one or more of X1, X2, L1, L2, n, L3, Z1, Z2, Z3, R1, and R2 may be attached to a support.
Other suitable complexes include Group 8 transition metal carbenes bearing a cationic substituent, such as are disclosed in U.S. Pat. No. 7,365,140 (Piers et al.) having the general structure (XIII):
wherein:
M is a Group 8 transition metal;
L1 and L2 are neutral electron donor ligands;
X1 and X2 are anionic ligands;
R1 is hydrogen, C1-C12 hydrocarbyl, or substituted C1-C12 hydrocarbyl;
W is an optionally substituted and/or heteroatom-containing C1-C20 hydrocarbylene linkage;
Y is a positively charged Group 15 or Group 16 element substituted with hydrogen, C1-C12 hydrocarbyl, substituted C1-C12 hydrocarbyl; heteroatom-containing C1-C12 hydrocarbyl, or substituted heteroatom-containing hydrocarbyl;
Z− is a negatively charged counterion;
m is zero or 1; and
n is zero or 1;
W is an optionally substituted and/or heteroatom-containing C1-C20 hydrocarbylene linkage, typically an optionally substituted C1-C12 alkylene linkage, e.g., —(CH2)i— where i is an integer in the range of 1 to 12 inclusive and any of the hydrogen atoms may be replaced with a non-hydrogen substituent as described earlier herein with regard to the definition of the term “substituted.” The subscript n is zero or 1, meaning that W may or may not be present. In a preferred embodiment, n is zero.
Y is a positively charged Group 15 or Group 16 element substituted with hydrogen, C1-C12 hydrocarbyl, substituted C1-C12 hydrocarbyl, heteroatom-containing C1-C12 hydrocarbyl, or substituted heteroatom-containing hydrocarbyl. Preferably, Y is a C1-C12 hydrocarbyl-substituted, positively charged Group 15 or Group 16 element. Representative Y groups include P(R2)3, P(R2)3, As(R2)3, S(R2)2, O(R2)2, where the R2 are independently selected from C1-C12 hydrocarbyl; within these, preferred Y groups are phosphines of the structure P(R2)3 wherein the R2 are independently selected from C1-C12 alkyl and aryl, and thus include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, cyclopentyl, cyclohexyl, and phenyl. Y can also be a heterocyclic group containing the positively charged Group 15 or Group 16 element. For instance, when the Group 15 or Group 16 element is nitrogen, Y may be an optionally substituted pyridinyl, pyrazinyl, or imidazolyl group.
Z− is a negatively charged counterion associated with the cationic complex, and may be virtually any anion, so long as the anion is inert with respect to the components of the complex and the reactants and reagents used in the metathesis reaction catalyzed. Preferred Z− moieties are weakly coordinating anions, such as, for instance, [B(C6F5)4]−, [BF4]−, [B(C6H6)4]−, [CF3S(O)3]−, [PF6]−, [SbF6]−, [AlCl4]−, [FSO3]−, [CB11H6Cl6]−, [CB11H6Br6]−, and [SO3F:SbF5]−. Preferred anions suitable as Z− are of the formula B(R15)4− where R15 is fluoro, aryl, or perfluorinated aryl, typically fluoro or perfluorinated aryl. Most preferred anions suitable as Z− are BF4− and B(C6F5)−, optimally the latter.
It should be emphasized that any two or more of X1, X2, L1, L2, R1, W, and Y can be taken together to form a cyclic group, as disclosed, for example, in U.S. Pat. No. 5,312,940 to Grubbs et al. When any of X1, X2, L1, L2, R1, W, and Y are linked to form cyclic groups, those cyclic groups may be five- or six-membered rings, or may comprise two or three five- or six-membered rings, which may be either fused or linked. The cyclic groups may be aliphatic or aromatic, and may be heteroatom-containing and/or substituted, as explained in part (I) of this section.
One group of exemplary catalysts encompassed by the structure of formula (XIII) are those wherein m and n are zero, such that the complex has the structure of formula (XIV)
Possible and preferred X1, X2, and L1 ligands are as described earlier with respect to complexes of formula (I), as are possible and preferred Y+ and Z− moieties. M is Ru or Os, preferably Ru, and R1 is hydrogen or C1-C12 alkyl, preferably hydrogen.
In formula (XIV)-type catalysts, L1 is preferably a heteroatom-containing carbene ligand having the structure of formula (XV)
such that complex (XIV) has the structure of formula (XVI)
wherein X1, X2, R1, R2, Y, and Z are as defined previously, and the remaining substituents are as follows:
Z1 and Z2 are heteroatoms typically selected from N, O, S, and P. Since O and S are divalent, j is necessarily zero when Z1 is O or S, and k is necessarily zero when Z2 is O or S. However, when Z1 is N or P, then j is 1, and when Z2 is N or P, then k is 1. In a preferred embodiment, both Z1 and Z2 are N.
Q1, Q2, Q3, and Q4 are linkers, e.g., C1-C12 hydrocarbylene, substituted C1-C12 hydrocarbylene, heteroatom-containing C1-C12 hydrocarbylene, substituted heteroatom-containing C1-C12 hydrocarbylene, or —(CO)—, and w, x, y, and z are independently zero or 1, meaning that each linker is optional. Preferably, w, x, y, and z are all zero.
R3, R3A, R4, and R4A are independently selected from hydrogen, hydrogen, C1-C20 hydrocarbyl, substituted C1-C20 hydrocarbyl, heteroatom-containing C1-C20 hydrocarbyl, and substituted heteroatom-containing C1-C20 hydrocarbyl.
Preferably, w, x, y, and z are zero, Z1 and Z1 are N, and R3A and R4A are linked to form -Q-, such that the complex has the structure of formula (XVII)
wherein R3 and R4 are defined above, with preferably at least one of R3 and R4, and more preferably both R3 and R4, being alicyclic or aromatic of one to about five rings, and optionally containing one or more heteroatoms and/or substituents. Q is a linker, typically a hydrocarbylene linker, including C1-C12 hydrocarbylene, substituted C1-C12 hydrocarbylene, heteroatom-containing C1-C12 hydrocarbylene, or substituted heteroatom-containing C1-C12 hydrocarbylene linker, wherein two or more substituents on adjacent atoms within Q may be linked to form an additional cyclic structure, which may be similarly substituted to provide a fused polycyclic structure of two to about five cyclic groups. Q is often, although not necessarily, a two-atom linkage or a three-atom linkage, e.g., —CH2—CH2—, —CH(Ph)—CH(Ph)— where Ph is phenyl; ═CR—N═, giving rise to an unsubstituted (when R═H) or substituted (R=other than H) triazolyl group; or —CH2—SiR2—CH2— (where R is H, alkyl, alkoxy, etc.).
In a more preferred embodiment, Q is a two-atom linkage having the structure —CR8R9—CR10R11— or —CR═CR10—, preferably —CR8R9—CR10R11—, wherein R8, R9, R10, and R11 are independently selected from hydrogen, C1-C12 hydrocarbyl, substituted C1-C12 hydrocarbyl, heteroatom-containing C1-C12 hydrocarbyl, substituted heteroatom-containing C1-C12 hydrocarbyl, and functional groups as defined in part (I) of this section. Examples of functional groups here include carboxyl, C1-C20 alkoxy, C5-C20 aryloxy, C2-C20 alkoxycarbonyl, C2-C20 alkoxycarbonyl, C2-C20 acyloxy, C1-C20 alkylthio, C5-C20 arylthio, C1-C20 alkylsulfonyl, and C1-C20 alkylsulfinyl, optionally substituted with one or more moieties selected from C1-C10 alkyl, C1-C10 alkoxy, C5-C20 aryl, hydroxyl, sulfhydryl, formyl, and halide. Alternatively, any two of R8, R9, R10, and R11 may be linked together to form a substituted or unsubstituted, saturated or unsaturated ring structure, e.g., a C4-C12 alicyclic group or a C5 or C6 aryl group, which may itself be substituted, e.g., with linked or fused alicyclic or aromatic groups, or with other substituents.
Further details concerning such formula (XIII) complexes, as well as associated preparation methods, may be obtained from U.S. Pat. No. 7,365,140, herein incorporated by reference.
As is understood in the field of catalysis, suitable solid supports for any of the catalysts described herein may be of synthetic, semi-synthetic, or naturally occurring materials, which may be organic or inorganic, e.g., polymeric, ceramic, or metallic. Attachment to the support will generally, although not necessarily, be covalent, and the covalent linkage may be direct or indirect, if indirect, typically through a functional group on a support surface.
Non-limiting examples that may be used in the reactions of the disclosure include the following, some of which for convenience are identified throughout this disclosure by reference to their molecular weight:
In the foregoing molecular structures and formulae, Ph represents phenyl, Cy represents cyclohexane, Me represents methyl, nBu represents n-butyl, i-Pr represents isopropyl, py represents pyridine (coordinated through the N atom), and Mes represents mesityl (i.e., 2,4,6-trimethylphenyl).
Further examples of catalysts useful in the reactions of the present disclosure include the following: ruthenium (II) dichloro (3-methyl-1,2-butenylidene)bis(tricyclopentylphosphine) (C716); ruthenium (II) dichloro (3-methyl-1,2-butenylidene) bis(tricyclohexylphosphine) (C801); ruthenium (II) dichloro (phenylmethylene)bis(tricyclohexylphosphine) (C823); ruthenium (II) [1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene)dichloro (phenylmethylene) (triphenylphosphine) (C830), and ruthenium (II) dichloro (vinyl phenylmethylene)bis(tricyclohexylphosphine) (C835); ruthenium (II) dichloro (tricyclohexylphosphine) (o-isopropoxyphenylmethylene) (C601), and ruthenium (II) (1,3-bis-(2, 4, 6,-trimethylphenyl)-2-imidazolidinylidene)dichloro (phenylmethylene) (bis 3-bromopyridine (C884)).
Exemplary ruthenium-based metathesis catalysts include those represented by structures 12 (commonly known as Grubbs's catalyst), 14 and 16. Structures 18, 20, 22, 24, 26, 28, 60, 62, 64, 66, and 68 represent additional ruthenium-based metathesis catalysts. Catalysts C627, C682, C697, C712, and C827 represent still additional ruthenium-based catalysts. General structures 50 and 52 represent additional ruthenium-based metathesis catalysts of the type reported in Chemical & Engineering News; Feb. 12, 2007, at pages 37-47. In the structures, Ph is phenyl, Mes is mesityl, py is pyridine, Cp is cyclopentyl, and Cy is cyclohexyl.
Techniques for using the metathesis catalysts are known in the art (see, for example, U.S. Pat. Nos. 7,102,047; 6,794,534; 6,696,597; 6,414,097; 6,306,988; 5,922,863; 5,750,815; and metathesis catalysts with ligands in U.S. Publication No. 2007/0004917 A1), all incorporated by reference herein in their entireties. A number of the metathesis catalysts as shown are manufactured by Materia, Inc. (Pasadena, Calif.).
Additional exemplary metathesis catalysts include, without limitation, metal carbene complexes selected from the group consisting of molybdenum, osmium, chromium, rhenium, and tungsten. The term “complex” refers to a metal atom, such as a transition metal atom, with at least one ligand or complexing agent coordinated or bound thereto. Such a ligand typically is a Lewis base in metal carbene complexes useful for alkene, alkyne or alkene-metathesis. Typical examples of such ligands include phosphines, halides and stabilized carbenes. Some metathesis catalysts may employ plural metals or metal co-catalysts (e.g. a catalyst comprising a tungsten halide, a tetraalkyl tin compound, and an organoaluminum compound).
An immobilized catalyst can be used for the metathesis process. An immobilized catalyst is a system comprising a catalyst and a support, the catalyst associated with the support. Exemplary associations between the catalyst and the support may occur by way of chemical bonds or weak interactions (e.g. hydrogen bonds, donor acceptor interactions) between the catalyst, or any portions thereof, and the support or any portions thereof. Support is intended to include any material suitable to support the catalyst. Typically, immobilized catalysts are solid phase catalysts that act on liquid or gas phase reactants and products. Exemplary supports are polymers, silica, or alumina. Such an immobilized catalyst may be used in a flow process. An immobilized catalyst can simplify purification of products and recovery of the catalyst so that recycling the catalyst may be more convenient.
The metathesis process for producing industrial chemicals can be conducted under any conditions adequate to produce the desired metathesis product or products. For example, stoichiometry, atmosphere, solvent, temperature and pressure can be selected to produce a desired product and to minimize undesirable byproducts. The metathesis process may be conducted under an inert atmosphere. Similarly, if an olefin reagent is supplied as a gas, an inert gaseous diluent can be used. The inert atmosphere or inert gaseous diluent typically is an inert gas, meaning that the gas does not interact with the metathesis catalyst to substantially impede catalysis. For example, particular inert gases are selected from the group consisting of helium, neon, argon, nitrogen, and combinations thereof.
Similarly, if a solvent is used, the solvent chosen may be selected to be substantially inert with respect to the metathesis catalyst. For example, substantially inert solvents include, without limitation, aromatic hydrocarbons, such as benzene, toluene, xylenes, etc.; halogenated aromatic hydrocarbons, such as chlorobenzene and dichlorobenzene; aliphatic solvents, including pentane, hexane, heptane, cyclohexane, etc.; and chlorinated alkanes, such as dichloromethane, chloroform, dichloroethane, etc.
In certain embodiments, a ligand may be added to the metathesis reaction mixture. In many embodiments using a ligand, the ligand is selected to be a molecule that stabilizes the catalyst, and may thus provide an increased turnover number for the catalyst. In some cases the ligand can alter reaction selectivity and product distribution. Examples of ligands that can be used include Lewis base ligands, such as, without limitation, trialkylphosphines, for example tricyclohexylphosphine and tributyl phosphine; triarylphosphines, such as triphenylphosphine; diarylalkylphosphines, such as, diphenylcyclohexylphosphine; pyridines, such as 2,6-dimethylpyridine, 2,4,6-trimethylpyridine; as well as other Lewis basic ligands, such as phosphine oxides and phosphinites. Additives may also be present during metathesis that increase catalyst lifetime.
Using currently known catalysts, the metathesis processing temperature may largely be a rate-dependent variable where the temperature is selected to provide a desired product at an acceptable production rate. The selected temperature may be greater than about −40° C., may be more than about −20° C., and is generally selected to be more than about 0° C. or more than about 20° C. Generally, the process temperature may be no more than about 150° C., and may be no more than about 120° C. Thus, an exemplary temperature range for the metathesis reaction may be from about 20° C. to about 120° C. Lower temperatures can be used, for example, to minimize the production of undesired impurities or to favor a particular reaction pathway.
Any useful amount of the selected metathesis catalyst can be used in the process. For example, the molar ratio of the unsaturated polyol ester to catalyst may range from about 5:1 to about 10,000,000:1 or from about 50:1 to 500,000:1.
The metathesis process steps (i.e., step (b) and step (d)) can be conducted under any desired pressure. For example, the cross-metathesis step (b) is typically conducted at a pressure ranging from about 10 kPa to about 7000 kPa or from about 100 kPa to about 3000 kPa. In some embodiments, it is preferred to conduct the self-metathesis step (i.e., step (d)) at low pressure, for example, about 0.01 kPa to about 100 kPa, more typically about 0.01 kPa to about 50 kPa. By conducting the self-metathesis at low pressure, the low boiling point olefin products (e.g., the short-chain internal olefin or alpha olefin) that are formed during the cross-metathesis reaction can be easily separated from the higher boiling point functionalized olefin products (e.g., the one or more diacid olefins, diester olefins, or disalt olefins). This separation is advantageous for two reasons. First, in an integrated process, the separation of the short-chain internal olefin product allows this material to be recycled back to the reactor where the cross-metathesis step (i.e., step (b)) is being conducted. Second, the removal of the olefin products from the functionalized olefin products drives the equilibrium of the self-metathesis reaction (i.e., step (d)) to the formation of more functionalized olefin product. This results in a higher yield of the desired functionalized olefin product.
The metathesis reaction may be catalyzed by a system containing both a transition and a non-transition metal component. The most active and largest number of two-part catalyst systems are derived from Group VI A transition metals, for example, tungsten and molybdenum.
After cross-metathesis with a short-chain olefin, at least a portion of the acid-, ester-, or carboxylate salt-functionalized alkene is separated from the remaining cross-metathesis products. If cross-metathesis is conducted on an unsaturated glyceride starting composition the resulting cross-metathesis products should be transesterified prior to separation. This allows the separation step to separate the ester-functionalized alkene from any ester functionalized alkane that may be present in the transesterification products.
Useful techniques for separating the acid-, ester-, or carboxylate salt-functionalized alkene from the remaining cross-metathesis products include, for example, distillation, reactive distillation, chromatography, fractional crystallization, membrane separation, liquid/liquid extraction, or a combination thereof.
In many embodiments, the acid-, ester-, or carboxylate salt-functionalized alkene can be purified to a high degree using one or more of the above-described techniques. For example, the acid-, ester-, or carboxylate salt-functionalized alkene can be purified to a level of 90% wt. or greater (e.g., 95% wt. or greater, 96% wt. or greater, 97% wt. or greater, 98% wt. or greater, 99% wt. or greater, 99.5% wt. or greater, or 99.9% wt. or greater). Using the method of the invention, a high purity functionalized alkene intermediate can be obtained using one or more conventional separation processes. Achieving a high purity functionalized alkene intermediate allows for the production of a high purity products from the methods of the invention For example, in some embodiments, the product has a purity of 90% wt. or greater (e.g., 95% wt. or greater, 96% wt. or greater, 97% wt. or greater, 98% wt. or greater, 99% wt. or greater, 99.5% wt. or greater, or 99.9% wt. or greater).
In some embodiments, after separation, the isolated acid-, ester-, or salt-functionalized alkene is self-metathesized in the presence of a metathesis catalyst to form a composition comprising one or more diacid alkenes, diester alkenes, or dicarboxylate salt alkenes. For example, when a Δ9 acid-functionalized starting composition is used and is cross-metathesized with 2-butene, the resulting acid-functionalized alkene has the structure HOOC—(CH2)7—CH═CH—CH3. After separation, self-metathesis of the acid-functionalized alkene yields an unsaturated C18 diacid and 2-butene according to the formula below:
2 HOOC—(CH2)7—CH═CH—CH3→HOOC—(CH2)7—CH═CH—(CH2)7—COOH+CH3—CH═CH—CH3
In similar fashion, when a Δ9 methyl ester-functionalized starting composition is used and is cross-metathesized with 2-butene, the resulting methyl ester-functionalized alkene has structure CH3OOC—(CH2)7—CH═CH—CH3. Self-metathesis of the ester-functionalized olefin yields an unsaturated C18 diester and 2-butene according to the formula below:
2CH3OOC—(CH2)7—CH═CH—CH3→CH3OOC—(CH2)7—CH═CH—(CH2)7—COOCH3+CH3—CH═CH—CH3
In another embodiment, a Δ5 acid-functionalized starting composition is used and is cross-metathesized with 2-butene to provide an acid-functionalized alkene having the structure HOOC—(CH2)3—CH═CH—CH3. Self-metathesis of the acid-functionalized alkene yields an unsaturated C10 diacid and 2-butene according to the formula below:
2HOOC—(CH2)3—CH═CH—CH3→HOOC—(CH2)3—CH═CH—(CH2)3—COOH+CH3—CH═CH—CH3
In another embodiment, a Δ6 acid-functionalized starting composition is used and is cross-metathesized with 2-butene to provide an acid-functionalized alkene having the structure HOOC—(CH2)4—CH═CH—CH3. Self-metathesis of the ester-functionalized alkene yields an unsaturated C12 diacid and 2-butene according to the formula below:
2HOOC—(CH2)4—CH═CH—CH3→HOOC—(CH2)4—CH═CH—(CH2)4—COOH+CH3—CH═CH—CH3
In another embodiment, a Δ13 acid-functionalized starting composition is used and is cross-metathesized with 2-butene to provide an acid-functionalized alkene having the structure HOOC—(CH2)11—CH═CH—CH3. Self-metathesis of the ester-functionalized alkene yields an unsaturated C26 diacid and 2-butene according to the formula below:
2HOOC—(CH2)11—CH═CH—CH3→HOOC—(CH2)11—CH═CH—(CH2)11—COOH+CH3—CH═CH—CH3
Other self-metathesis reactions would follow the above reaction scheme.
In some embodiments, after separation, the isolated acid-, ester-, or carboxylate salt-functionalized alkene is cross-metathesized with a second functionalized alkene compound in the presence of a metathesis catalyst to form a bifunctional organic compound. Exemplary bifunctional organic compounds obtainable by this method include diacids, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, as well as diesters, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, and ester/nitriles. In many embodiments, after cross-metathesis, the resulting bifunctional organic compound is hydrogenated in order to saturate the double-bond that is present in the bifunctional compound. For example, starting with fatty acids □5 and higher, alpha,omega-diacids from C7 to C18 and higher can be made. Similarly, omega-hydroxycarboxylic acids and omega-aminocarboxylic acids from C7 to C18 and higher can be made.
The second functionalized alkene compound has at least one carbon-carbon double bond and has at least one organic functional group. Examples of organic functional groups include carboxylic acids, esters, amines, amides, halogens, aldehydes, nitriles, isocyanates, ketones, epoxides, and alcohols. In many embodiments, the second functionalized alkene has the general structure:
R12—CH═CH—(CH2)n—R13
where
Examples of second functionalized alkene compounds include 2-butene-1,4-dioic acid (HOOCCH═CHCOOH), acrylic acid (CH═CHCOOH), 2-butenoic acid (CH3CH═CHCOOH), 2-pentenoic acid (CH3CH2CH═CHCOOH), 2-hexenoic acid (CH3CH2CH2CH═CHCOOH), 3-hexenedioc acid (HOOCCH2CH═CHCH2COOH), the dimethyl ester of 3-hexenedioc acid (CH3OOCCH2CH═CHCH2COOCH3), 3-hexenoic acid (HOOCCH2CH═CHCH2CH3), the methyl ester of 3-hexenoic acid (CH3OOCCH2CH═CHCH2CH3), 3-pentenoic acid (HOOCCH2CH═CHCH3), methyl ester of 3-pentenoic acid (CH3OOCCH2CH═CHCH3), 4-pentenoic acid, 4-hexenoic acid, 4-heptenoic acid, 4-octenoic acid and its esters, 4-octene-1,8-dioic acid and its esters, 5-hexenoic acid, 1-bromo-3 hexene, 3-butenal diethyl acetal, 5-heptenoic acid, 5-octenoic acid and its esters, 5-decene-1,10-dioic acid and its esters, 6-heptenoic acid, 6-octenoic acid, 6-nonenoic acid, 6-decenoic acid and its esters, 6-dodecene-1,12-dioic acid and its esters, 7-octenoic acid, 7-nonenoic acid, 7-decenoic acid, 7-undecenoic acid, and 7-dodecenoic acid and its esters.
Additional examples of second functionalized alkene compounds include allyl alcohol, 2-butenol, 3-buten-1-ol, 2-penten-1-ol, 3-penten-1-ol, 4-penten-1-ol, 2-hexen-1-ol, 3-hexen-1-ol, 4-hexen-1-ol, 5-hexen-1-ol, and the like; buten-1,4-diol, 2-penten-1,5-diol, 2-hexen-1,6-diol, 3-hexen-1,6-diol, and the like; allyl amine, 1-amino-2-butene, 1-amino-3-butene, 1-amino-2-pentene, 1-amino-3-pentene, 1-amino-4-pentene, 1-amino-2-hexene, 1-amino-3-hexene, 1-amino-4 hexene, 1-amino-5-hexene, and the like; 1,4-diamino-2-butene, 1,5-diamino-2-pentene, 1,6-diamino-2-hexene, 1,6-diamino-3-hexene, and the like; 1-chloro-2-propene (i.e., allyl chloride), 1-chloro-2-butene, 1-chloro-3-butene, 1-chloro-2-pentene, 1-chloro-3-pentene, 1-chloro-4-pentene, 1-chloro-2-hexene, 1-chloro-3-hexene, 1-chloro-4-hexene, 1-chloro-5-hexene, and the like (including the F, Br, or I analogs); 1,4-dichloro-2-butene (Cl—CH2—CH═CH—CH2—Cl), 1,5-dichloro-2-pentene, 1,6-dichloro-2-hexene, 1,6-dichloro-3-hexene, and the like (including the F, Br, or I analogs); acrolein (propenal), 2-butenal, 3-butenal, 2-pentenal, 3-pentenal, 4-pentenal, 2-hexenal, 3-hexenal, 4-hexenal, 5-hexenal, and the like; 2-buten-1,4-dial, 2-penten-1,5-dial, 2-hexen-1,6-dial, 3-hexen-1,6-dial, and the like; acrylonitrile (cyanoethylene), 1-cyano-1-propene, 1-cyano-2-propene, 1-cyano-1-butene, 1-cyano-2-butene, 1-cyano-3-butene, 1-cyano-1-pentene, 1-cyano-2-pentene, 1-cyano-3-pentene, and the like; 1,2-dicyanoethylene, 1,3-dicyanopropene, 1,4-dicyano-1-butene, 1,4-dicyano-2-butene, and the like.
In exemplary embodiments, the second functionalized alkene is symmetric about its carbon-carbon double bond. That is, the group —R12 is the same as group —(CH2)n—R13. Advantageously, when the second functionalized alkene is symmetric, the number of products formed in the cross-metathesis reaction is reduced as compared to cross-metathesis reactions where the second functionalized alkene is asymmetric. This may provide for higher yields and/or easier separation of the desired bifunctional compound. Representative examples of symmetric functionalized alkenes include maleic acid (HO2CCH═CHCO2H) and esters thereof, 3-hexenedioc acid (HO2CCH2CH═CHCH2CO2H) and esters thereof (e.g., the dimethyl ester of 3-hexenedioc acid (CH3O2CCH2CH═CHCH2CO2CH3)), 4-octene-1,8-dioic acid and esters thereof, 5-decene-1,10-dioic acid and esters thereof, and 6-dodecene-1,12-dioic acid esters.
In an exemplary embodiment, a Δ9 acid-functionalized starting composition is used and is cross-metathesized with 2-butene, providing an acid-functionalized alkene having the structure HO2C—(CH2)7—CH═CH—CH3. After separation, the acid-functionalized alkene is cross-metathesized with 3-hexenedioc acid (HO2CCH2CH═CHCH2CO2H) in the presence of a metathesis catalyst. The cross-metathesis yields an unsaturated C12 diacid according to the formula below:
HO2C—(CH2)7—CH═CH—CH3+HO2CCH2CH═CHCH2CO2H→HO2C—(CH2)7—CH═CH—CH2—CO2H+CH3—CH═CHCH2CO2H
Optionally, the unsaturated C12 diacid may be hydrogenated to produce the corresponding saturated C12 diacid.
In another exemplary embodiment, a Δ9 acid-functionalized starting composition is used and is cross-metathesized with 2-butene, providing an acid-functionalized alkene having the structure HO2C—(CH2)7—CH═CH—CH3. After separation, the acid-functionalized alkene is cross-metathesized with maleic acid (HO2C—CH═CH—CO2H) in the presence of a metathesis catalyst. The cross-metathesis yields an unsaturated C11 diacid according to the formula below:
HO2C—(CH2)7—CH═CH—CH3+HO2C—CH═CH—CO2H→HO2C—(CH2)7—CH═CH—CO2H+CH3—CH═CH—CO2H
Other examples of bifunctional organic products that may be made using the method of the invention are summarized in TABLES C-D.
Optionally, the above-listed unsaturated compounds may be hydrogenated to form the corresponding saturated compounds.
After self- or cross-metathesis (i.e., step (d)), the resulting alkene may be hydrogenated to remove the carbon-carbon double bond. Hydrogenation is typically conducted by exposing the alkene to H2 gas in the presence of a hydrogenation catalyst.
The principal component of the catalyst useful for the hydrogenation is selected from metals from the group consisting of palladium, ruthenium, rhenium, rhodium, iridium, platinum, nickel, cobalt, copper, iron, osmium; compounds thereof; and combinations thereof.
The catalyst may be supported or unsupported. A supported catalyst is one in which the active catalyst agent is deposited on a support material by a number of methods, such as spraying, soaking or physical mixing, followed by drying, calcination, and if necessary, activation through methods such as reduction or oxidation. Materials frequently used as a support are porous solids with high total surface areas (external and internal), which can provide high concentrations of active sites per unit weight of catalyst. The catalyst support may enhance the function of the catalyst agent. A supported metal catalyst is a supported catalyst in which the catalyst agent is a metal.
A catalyst that is not supported on a catalyst support material is an unsupported catalyst. An unsupported catalyst may be platinum black or a Raney™ (W.R. Grace & Co., Columbia, Md.) catalyst. Raney™ catalysts have a high surface area due to selectively leaching an alloy containing the active metal(s) and a leachable metal (usually aluminum). Raney® catalysts have high activity due to the higher specific area and allow the use of lower temperatures in hydrogenation reactions. The active metals of Raney™ catalysts include nickel, copper, cobalt, iron, rhodium, ruthenium, rhenium, osmium, iridium, platinum, palladium; compounds thereof; and combinations thereof.
The catalyst support useful herein can be any solid, inert substance including, but not limited to, oxides such as silica, alumina and titania; barium sulfate; calcium carbonate; and carbons. The catalyst support can be in the form of powder, granules, pellets, or the like.
A preferred support material of the invention is selected from the group consisting of carbon, alumina, silica, silica-alumina, silica-titania, titania, titania-alumina, barium sulfate, calcium carbonate, strontium carbonate, compounds thereof and combinations thereof. Supported metal catalysts can also have supporting materials made from one or more compounds. More preferred supports are carbon, titania and alumina. Further preferred supports are carbons with a surface area greater than 100 m2/g. A further preferred support is carbon with a surface area greater than 200 m2/g. Preferably, the carbon has an ash content that is less than 5% by weight of the catalyst support; the ash content is the inorganic residue (expressed as a percentage of the original weight of the carbon) which remains after incineration of the carbon.
The preferred content of the metal catalyst in the supported catalyst is from about 0.1% to about 20% of the supported catalyst based on metal catalyst weight plus the support weight. A more preferred metal catalyst content range is from about 1% to about 10% of the supported catalyst.
Combinations of metal catalyst and support system may include any one of the metals referred to herein with any of the supports referred to herein. Preferred combinations of metal catalyst and support include palladium on carbon, palladium on calcium carbonate, palladium on barium sulfate, palladium on alumina, palladium on titania, platinum on carbon, platinum on alumina, platinum on silica, iridium on silica, iridium on carbon, iridium on alumina, rhodium on carbon, rhodium on silica, rhodium on alumina, nickel on carbon, nickel on alumina, nickel on silica, rhenium on carbon, rhenium on silica, rhenium on alumina, ruthenium on carbon, ruthenium on alumina and ruthenium on silica.
Further preferred combinations of metal catalyst and support include palladium on carbon, palladium on alumina, palladium on titania, platinum on carbon, platinum on alumina, rhodium on carbon, rhodium on alumina, ruthenium on carbon and ruthenium on alumina.
The method of the invention will now be described with reference to
If the starting material comprises a fatty ester in glyceride form, the glyceride may be converted (e.g., by transesterification) into free fatty esters prior to being cross-metathesized with the short-chain internal olefin, or the glyceride can be cross-metathesized with the short-chain internal olefin followed by conversion (e.g., by transesterification) into free fatty esters.
Referring now to
After separation, a cross-metathesis reaction 118 is conducted between the free fatty esters 110 and short-chain internal olefin 116. The cross-metathesis 118 is conducted in the presence of a metathesis catalyst 120 in order to form cross-metathesis products 122 comprising one or more olefins 124 and one or more ester-functionalized alkenes 126. Following this, at least a portion of the ester-functionalized alkenes 126 are separated 128 (e.g., using distillation) from the cross-metathesis products 122. The isolated ester-functionalized alkene 126 is then self-metathesized 129 in the presence of a second metathesis catalyst 130 to produce the self-metathesis products 132 comprising a diester alkene 134 and one or more olefin products 136.
Referring to
In an exemplary embodiment, as shown in
In another exemplary embodiment, as shown in
The invention will now be described with reference to the following non-limiting examples.
Metathesis reactions were conducted in a 250 ml 3-neck round bottom Schlenk flask that was equipped with a reflux condenser (connected to a bubbler), two septa, a stir bar, and a thermocouple. Prior to adding any reactants, the apparatus was degassed with argon for thirty minutes. Then, 70 ml (64.4 g) of degassed soybean oil (Cargill soybean oil (Salad oil), Lot # F4102) was added to the apparatus. In a separate container, 3-hexene was degassed with argon for one hour. Following degassing, 127 ml (86.4 grams) of the degassed 3-hexene was added to the flask using a graduated cylinder. The resulting mixture was degassed for fifteen minutes with argon. The mixture was then heated to 65° C. before adding the metathesis catalyst.
Metathesis catalyst (C827, Lot # 067-050B) was added to the degassed mixture of soybean oil and 3-hexene in the amount shown in TABLE 1. In each case, the resulting mixture was allowed to react at 65° C., with aliquots taken at 2, 4, and 6 hours to check for conversion using a gas chromatograph. Maximum conversion was reached after two hours in all cases. In each case, after reacting for 6 hours, 1.30 grams of activated clay (Pure-Flo B80 natural Bleaching Adsorbent) was added, and the resulting composition was stirred overnight. Following this, the composition was filtered through a bed of silica to remove the activated clay and metathesis catalyst. The filtrates were sealed in a sample bottle and refrigerated. Percent yield of methyl 9-dodecenoate was determined using a gas chromatograph. The resulting data is presented in TABLE 1.
1Catalyst 827 loading in ppm per double bond of SBO. 3-Hexene was added in 3 equivalents per double bond of SBO.
2GC yield after 2 hours, yields did not change significantly at 6 hours.
Samples of methyl 9-dodecenoate were warmed to temperature (see, TABLE 2) and were degassed with argon for 30 minutes. Next, a metathesis catalyst (see, TABLE 2) was added to the methyl 9-dodecenoate and vacuum was applied to provide a pressure of <1 mmHg. The methyl 9-dodecenoate was then allowed to self-metathesize for the time reported in TABLE 2. GC analysis indicated that 1,18-dimethyl ester of 9-octadecene [CH3O2C(CH2)7CH═CH(CH2)7CO2CH3] was produced in the yield reported in TABLE 2.
A glass 2.0 L 3-necked round bottom flask with a magnetic stirrer, packed 5 column, distillation head, and temperature controller was charged with esterified products and was placed in a heating mantle. The flask was attached to a 2-inch×36-inch glass distillation packed column containing 0.16″ Pro-Pak™ stainless steel saddles. The distillation column was connected to a fractional distillation head, which was connected to a vacuum line. A 500 mL pre-weighed round bottom flask was used to collect the distilled fractions. During distillation, vacuum was applied to provide a pressure of <1 mmHg. TABLE 3 contains the vacuum distillation results.
6C15+6,9C15 impurities were separated from 9C12O2Me by equilibrating the distillation column for 24 hours, followed by collecting 6C15+6,9C15 with a reflux ratio of 1:10 (i.e. 1 drop collected for every 10 drops sent back to the packed column). This procedure demonstrates that 9C12O2Me (275.4 g.) could be isolated in 50.9% yield and in 99.2% chemical purity. The 6C15+6,9C15 impurities could be removed by fractional distillation.
Methyl 9-decenoate (25 g, 114 mmol, ˜90% chemical purity) obtained by ethenolysis of methyl oleate was charged in a 250 mL round-bottomed flask and was degassed with argon for 30 min. C823 metathesis catalyst (127 mg, 0.15 mmol, 0.13 mol %) was then added, and the reaction contents were heated to 35° C. under vacuum for 16 hrs. A 1.0 M solution of tris(hydroxymethyl)phosphine (4 mL) was then added and the reaction contents were heated to 90° C. for 4 hr. The reaction contents were then cooled to room temperature and were diluted with 50 mL of ethyl acetate. The diluted reaction contents were then washed sequentially with (1) 50 mL of 1.0 M aqueous HCl, (2) water, and (3) brine. The resulting organic phase was then dried with anhydrous sodium sulfate, filtered, and concentrated by rotary evaporation. 1 gram of the crude diester (1,18-dimethyl 9-octadecenedioate) was then dissolved in 4.5 mL of hexanes and the resulting homogeneous solution was cooled to −11° C. for 5 hrs. The crystals that formed were filtered and air-dried. GC analysis of the crystals indicated 95.8% chemical purity and 99:1 E:Z isomeric ratio.
Step 1: Methyl-9-Dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-metathesis of Methyl 9-dodecenoate with Methyl-3-Pentenoate
Methyl 9-dodecenoate and methyl-3-pentenoate were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 4). Next, a metathesis catalyst (see, TABLE 4) was added to the methyl 9-dodecenoate and methyl-3-pentenoate mixture. The mixture was then allowed to metathesize for the time reported in TABLE 4. GC analysis indicated that 1,12-dimethyl ester of dodecene [CH3O2C(CH2)7CH═CH(CH2)CO2CH3] was produced in the GC yield reported in TABLE 4.
1No conversion was seen at lower catalyst loadings.
Step 1: Methyl-9-Dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-metathesis of methyl-9-dodecenoate with 1,4-dichloro-2-butene
Methyl 9-dodecenoate and 1,4-dichloro-2-butene were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 5). Next, a metathesis catalyst (see, TABLE 5) was added to the methyl 9-dodecenoate and 1,4-dichloro-2-butene mixture. The mixture was then allowed to metathesize for the time reported in TABLE 5. GC analysis indicated that the product [CH3O2C(CH2)7CH═CHCH2Cl] was produced in the GC yield reported in TABLE 5.
1827 was initiated at 60° C., then reaction removed from heat to stir at room temp. Freshly distilled 1,4-dichloro-2-butene was used.
21,4-dichloro-2-butene used directly from bottle with no distillation.
Step 1: Methyl 9-dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-Metathesis of methyl 9-dodecenoate with 3-buten-1-yl acetate.
Methyl 9-dodecenoate and 3-buten-1-yl acetate were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 6). Next, a metathesis catalyst (see, TABLE 6) was added to the methyl 9-dodecenoate and 3-buten-1-yl acetate mixture. The mixture was then allowed to metathesize for the time reported in TABLE 6. GC analysis indicated that the product [CH3O2C(CH2)7CH═CH(CH2)2CO2CH3] was produced in the GC yield reported in TABLE 6.
1827 was initiated at 60° C., then reaction removed from heat to stir at room temp.
Step 1: Methyl 9-dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-Metathesis of Methyl 9-dodecenoate with 3-buten-1-yl trimethylsilyl ether.
Methyl 9-dodecenoate and 3-buten-1-yl trimethylsilyl ether were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 7). Next, a metathesis catalyst (see, TABLE 7) was added to the methyl 9-dodecenoate and 3-buten-1-yl trimethylsilyl ether mixture. The mixture was then allowed to metathesize for the time reported in TABLE 7. GC analysis indicated that the product [CH3O2C(CH2)7CH═CH(CH2)2OSi(CH3)3] was produced in the GC yield reported in TABLE 7.
1827 was initiated at 60° C., then reaction removed from heat to stir at room temp.
Step 1: Methyl 9-dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-Metathesis of Methyl 9-dodecenoate with 1-bromo-3-hexene.
Methyl 9-dodecenoate and 1-bromo-3-hexene were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 8). Next, a metathesis catalyst (see, TABLE 8) was added to the methyl 9-dodecenoate and 1-bromo-3-hexene mixture. The mixture was then allowed to metathesize for the time reported in TABLE 8. GC analysis indicated that the product [CH3O2C(CH2)7CH═CH(CH2)2Br] was produced in the GC yield reported in TABLE 8.
Step 1: Methyl 9-dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-Metathesis of methyl 9-dodecenoate with Allyl chloride.
Methyl 9-dodecenoate and allyl chloride were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 9). Next, a metathesis catalyst (see, TABLE 9) was added to the methyl 9-dodecenoate and allyl chloride mixture. The mixture was then allowed to metathesize for the time reported in TABLE 9. GC analysis indicated that the product [CH3O2C(CH2)7CH═CHCH2Cl] was produced in the GC yield reported in TABLE 9.
Step 1: Methyl 9-dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Cross-Metathesis of methyl-9-dedecenoate with 3-butenal diethyl acetal.
Methyl 9-dodecenoate and 3-butenal diethyl acetal were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 10). Next, a metathesis catalyst (see, TABLE 10) was added to the methyl 9-dodecenoate and 3-butenal diethyl acetal mixture. The mixture was then allowed to metathesize for the time reported in TABLE 10. GC analysis indicated that the product [CH3O2C(CH2)7CH═CHCH2CH(OCH2CH3)2] was produced in the GC yield reported in TABLE 10.
Step 1: Methyl 9-dodecenoate was prepared as described in Step 1 of EXAMPLE 1.
Step 2: Cross-Metathesis of methyl-9-dodecenoate with 1-tert-butoxybut-3-ene.
Methyl 9-dodecenoate and 1-tert-butoxybut-3-ene were combined and degassed with argon for 30 minutes, then warmed to temperature (see, TABLE 11). Next, a metathesis catalyst (see, TABLE 11) was added to the methyl 9-dodecenoate and 1-tert-butoxybut-3-ene mixture. The mixture was then allowed to metathesize for the time reported in TABLE 11. GC analysis indicated that the product [CH3O2C(CH2)7CH═CH(CH2)2OC(CH3)3] was produced in the GC yield reported in TABLE 11.
Other embodiments of this invention will be apparent to those skilled in the art upon consideration of this specification or from practice of the invention disclosed herein. Various omissions, modifications, and changes to the principles and embodiments described herein may be made by one skilled in the art without departing from the true scope and spirit of the invention which is indicated by the following claims. All patents, patent documents, and publications cited herein are hereby incorporated by reference as if individually incorporated.
This application is a continuation-in-part of International Application No. PCT/US2007/021933, filed Oct. 15, 2007, which claims the benefit of U.S. Provisional Application having Ser. No. 60/851,632, filed Oct. 13, 2006, and entitled METHODS OF MAKING ORGANIC COMPOUNDS BY METATHESIS, the disclosures of which are incorporated herein by reference.
This invention was made with U.S. Government support under Award Number DE-FG36-04GO14016 awarded by the U.S. Department of Energy. The Government may have certain rights in this invention.
| Number | Date | Country | |
|---|---|---|---|
| 60851632 | Oct 2006 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2007/021933 | Oct 2007 | US |
| Child | 12422096 | US |
