SILYLATED OLIGOGERMANES AND POLYCYCLIC SILICON-GERMANIUM COMPOUNDS, PROCESSES FOR THEIR PREPARATION AND THEIR USE FOR THE PREPARATION OF A SI- AND GE-CONTAINING SOLID

Information

  • Patent Application
  • 20230219982
  • Publication Number
    20230219982
  • Date Filed
    June 01, 2021
    3 years ago
  • Date Published
    July 13, 2023
    a year ago
Abstract
The present invention relates to a compound of the formula (Ia) or the formula (Ib)
Description
FIELD OF THE INVENTION

The present invention relates to silylated oligogermanes and polycyclic silicon-germanium compounds, a process for their preparation and their use for the preparation of a Si- and Ge-containing solid.


BACKGROUND OF THE INVENTION

Halosilanes, polyhalosilanes, halogermanes, polyhalogermanes, silane, polysilanes, germane, polygermanes and corresponding mixed compounds have long been known, cf. WO 2004/036631 A2 or C. J. Ritter et al., J. Am. Chem. Soc., 2005, 127, 9855-9864.


Triphenylgermylsilane and its preparation is described in EP 3 409 645 A1.


Chlorosilylarylgermanes and their preparation are disclosed in EP 3 410 466.


Ritter et al. J. Am. Chem. Soc. 2005, 127, 9855 describes the use of (H3Ge)xSiH4-x for the preparation of semiconductor nanostructures on silicon.


Starting from the prior art, it is desirable to prepare improved silicon-germanium compounds, in particular storage-capable silicon-germanium compounds, and to provide a flexible process for the simple preparation of a large number of such compounds. It is also desirable to provide compounds which can be used to produce Si/Ge solids.


The object of the present invention is to overcome disadvantages of the prior art, in particular to prepare storage-capable, tailored silicon-germanium compounds which are suitable for the preparation of Si/Ge solids.


OVERVIEW OF THE INVENTION

This object is achieved by a compound of the formula (Ia) or (Ib)




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    • in which formula (Ia)
      • n is an integer from 1 to 10;
      • R1 and R2 are independently of each other selected from the group consisting of C1 to C20 alkyl, C2 to C20 alkenyl, C2 to C20 alkynyl, C3 to C20 cycloalkyl, C6 to C20 aryl, C7 to C20 arylalkyl and C7 to C20 alkylaryl; and
      • X1 is selected from the group consisting of H, SiH3, halogen and Si(Y1)3 with Y1=halogen;







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    • in which formula (Ib)
      • E1 to E6 are independently of each other Si or Ge;
      • X11 to X14 are independently of each other selected from the group consisting of H, SiH3, halogen and Si(Y2)3;
      • Y2 is independently selected from C1 to C20 alkyl and halogen;
      • R3 to R14 are independently of each other selected from the group consisting of C1 to C20 alkyl, C2 to C20 alkenyl, C2 to C20 alkynyl, C3 to C20 cycloalkyl, C6 to C20 aryl, C7 to C20 arylalkyl, C7 to C20 alkylaryl and Z; and
      • Z is independently selected from the group consisting of H, halogen and C1 to C20 alkyl.





A Compound of the Formula (Ia)


It may be provided that n is an integer from 1 to 8. It may further be provided that n is an integer from 1 to 6. It may further be provided that n is an integer from 1 to 4. It may also be provided that n is an integer from 2 to 10. It may also be provided that n is an integer from 2 to 8. It may also be provided that n is an integer from 2 to 6. It may also be provided that n is an integer from 2 to 5. Finally, it may be provided that n is an integer from 2 to 4.


It may be provided that R1 and R2 are independently of each other selected from the group consisting of C1 to C12 alkyl, C2 to C12 alkenyl, C2 to C12 alkynyl, C3 to C12 cycloalkyl, C6 to C12 aryl, C7 to C13 arylalkyl and C7 to C13 alkylaryl.


It may be provided that R1 and R2 are independently of each other selected from the group consisting of C1 to C12 alkyl, C6 to C12 aryl, C7 to C13 arylalkyl and C7 to C13 alkylaryl.


It may be provided that R1 and R2 are independently of each other selected from the group consisting of C1 to C20 alkyl and C6 to C20 aryl.


It may be provided that R1 and R2 are independently of each other selected from the group consisting of C1 to C12 alkyl and C6 to C12 aryl.


It may be provided that R1 and R2 are independently of each other phenyl or methyl.


It may be provided that R1 and R2 are the same. In this context, it may be provided that all R1 and R2 contained in the compound of the formula (Ia) are the same and are selected from one of the groups mentioned above.


It may be provided that X1 is selected from the group consisting of H, SiH3, Cl and SiCl3.


A Compound of the Formula (Ib)


It may be provided that at least three of E1 to E6 are Ge and the remaining of E1 to E6 are Si. It may be provided that four, five or six of E1 to E6 are Ge and the remaining of E1 to E6 are Si. It may be provided that four or five of E1 to E6 are Ge and the remaining of E1 to E6 are Si.


It may be provided that R3 to R14 are independently of each other selected from the group consisting of C1 to C12 alkyl, C2 to C12 alkenyl, C2 to C12 alkynyl, C3 to C12 cycloalkyl, C6 to C12 aryl, C7 to C13 arylalkyl, C7 to C13 alkylaryl and halogen.


It may be provided that R3 to R14 are independently of each other selected from the group consisting of C1 to C12 alkyl, C6 to C12 aryl, C7 to C13 arylalkyl, C7 to C13 alkylaryl and halogen.


It may be provided that R3 to R14 are independently of each other selected from the group consisting of C1 to C20 alkyl, C6 to C20 aryl and halogen.


It may be provided that R3 to R14 are independently of each other selected from the group consisting of C1 to C12 alkyl and halogen.


It may be provided that R3 to R14 are independently of each other Cl or methyl.


It may be provided that two Rn directly connected to the same Em (i.e., the two R in the pairs R3 and R4, R5 and R6, R7 and R8, R9 and R10, R11 and R12, and R13 and R14) are the same.


It may be provided that in the case that the Em (i.e., one of E1 to E6) is Ge, the two Rn directly connected to the Em are C1 to C20 alkyl. It may be provided that in the case that the Em (i.e., one of E1 to E6) is Ge, the two Rn directly connected to the Em are C1 to C12 alkyl. It may be provided that in the case that the Em (i.e., one of E1 to E6) is Ge, the two Rn directly connected to the Em are C1 to C8 alkyl. It may be provided that in the case that the Em (i.e., one of E1 to E6) is Ge, the two Rn directly connected to the Em are C1 to C4 alkyl. It may be provided that in the case that the Em (i.e., one of E1 to E6) is Ge, the two Rn directly connected to the Em are methyl.


It may be provided that in the case that the Em (i.e., one of E1 to E6) is Si, the two Rn directly connected to the Em are halogen. It may be provided that in the case that the Em (i.e., one of E1 to E6) is Si, the two Rn directly connected to the Em are Cl.


It may be provided that X11 to X14 are independently selected from the group consisting of H, SiH3, Si(C1 to C20 alkyl)3, Cl and SiCl3. It may be provided that X11 to X14 are independently of each other selected from the group consisting of H, SiH3, Si(C1 to C12 alkyl)3, Cl and SiCl3. It may be provided that X11 to X14 are independently of each other selected from the group consisting of H, SiH3, Si(C1 to C8 alkyl)3, Cl and SiCl3. It may be provided that X11 to X14 are independently of each other selected from the group consisting of H, SiH3, Si(C1 to C4 alkyl)3, Cl and SiCl3. It may be provided that X11 to X14 are independently of each other selected from the group consisting of Si(C1 to C4 alkyl)3 and SiCl3.


It may be provided that the compound of the formula (Ib) is selected from one of the following compounds C1 to C4.




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Process for Preparing a Compound of the Formula (Ia)


The object is further achieved by a process for preparing a compound of the formula (Ia) according to one of the preceding claims comprising reacting a compound of the formula (IIa)




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with a compound of the formula (IIIa)




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wherein X3 to X10 are independently halogen; and R1 and R2 are as defined above; and hydrogenating the product obtained by reacting the compound of the formula (IIa) with the compound of the formula (IIIa).


The ratio of compound (IIa) to compound (IIIa) can be from 10:1 to 1:20; 5:1 to 1:1; 2:1 to 1:10; 1.5:1 to 1:8; 1.2:1 to 1:5; 1:1 to 1:4.


It can be provided that the reaction of the compound of the formula (IIa) with the compound of the formula (IIIa) is carried out in the presence of a catalyst. It can be provided to use the catalyst in amounts of from 0.001 to 1 eq., preferably from 0.01 to 0.1 eq. It can be provided that the catalyst is a base. It can be provided that the catalyst is a base containing phosphorus or nitrogen. It can be provided that the catalyst is a base containing nitrogen. It can be provided that the catalyst is a phosphonium or ammonium salt. It can be provided that the catalyst is selected from [(R′)4P]Cl or [(R′)4N]Cl, wherein the radicals R′ are independently of each other selected from C1 to C12 alkyl, C6 to C12 aryl, C7 to C13 arylalkyl and C7 to C13 alkylaryl. It can be provided that the catalyst is [(R′)4N]Cl, wherein R′ is selected from methyl, ethyl, isopropyl, n-butyl and phenyl. It can be provided that the catalyst is [(R′)4N]Cl, wherein R′ is selected n-butyl.


It can be provided that the reaction of the compound of the formula (IIa) with the compound of the formula (IIIa) is carried out in a solvent. In the process, at least 5 mol of solvent can be used per mol of compound (IIIa), alternatively from 10 mol to 100 mol of solvent per mol of compound (IIIa). It can be provided that the solvent is an organic solvent. It can be provided that the solvent (both in the reaction step and in the hydrogenation step) is a non-polar organic solvent. It can be provided that the solvent is selected from n-pentane, n-hexane, n-heptane, cyclohexane, toluene, diethyl ether, dichloromethane, chloroform, tert-butyl methyl ether, acetone and tetrahydrofuran. It can be provided that the solvent is dichloromethane.


It can be provided that the reaction of the compound of the formula (IIa) with the compound of the formula (IIIa) is carried out at a temperature in a range from 0° C. to 50° C., 10° C. to 40° C., 15° C. to 30° C., 20° C. to 25° C., or 22° C. (=room temperature).


It can be provided that the reaction of the compound of the formula (IIa) with the compound of the formula (IIIa) is carried out for 5 min to 24 h, 30 min to 12 h, or 1 h to 4 h.


It can be provided that the hydrogenation of the product obtained by reacting the compound of the formula (IIa) with the compound of the formula (IIIa) is carried out by adding a hydrogenating agent. It can be provided that the hydrogenating agent is lithium aluminum hydride.


Process for Preparing a Compound of the Formula (Ib)


The object is further achieved by a process for preparing a compound of the formula (Ib) according to one of the preceding claims comprising reacting a compound of the formula (IIb)




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with a compound of the formula (IIIb)




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wherein Hal1 to Hal8 are independently halogen; and R3 and R4 are as defined above; and

    • crystallizing the product of the reaction of the compounds (IIb) and (IIIb).


It may be provided that in the process E1=Ge and E2 and E3 are each Si.


The molar ratio of compound (IIb) to compound (IIIb) can be from 10:1 to 1:40; 5:1 to 1:2; 2:1 to 1:20; 1.5:1 to 1:10; 1.2:1 to 1:8; 1:3 to 1:5, about 1:4.


It can be provided that the reaction of the compound of the formula (IIb) with the compound of the formula (IIIb) is carried out in the presence of a catalyst. It can be provided to use the catalyst in amounts of from 0.001 to 1 eq., preferably from 0.01 to 0.1 eq. It can be provided that the catalyst is a base. It can be provided that the catalyst is a base containing phosphorus or nitrogen. It can be provided that the catalyst is a base containing nitrogen. It can be provided that the catalyst is a phosphonium or ammonium salt. It can be provided that the catalyst is selected from [(R3)4P]Cl or [(R3)4N]Cl, wherein the radicals R3 are independently of each other selected from C1 to C12 alkyl, C6 to C12 aryl, C7 to C13 arylalkyl and C7 to C13alkylaryl. It can be provided that the catalyst is [(R3)4N]Cl, wherein R3 is selected from methyl, ethyl, isopropyl, n-butyl and phenyl. It can be provided that the catalyst is [(R3)4N]Cl, wherein R3 is selected n-butyl.


It can be provided that the reaction of the compound of the formula (IIb) with the compound of the formula (IIIb) is carried out in a solvent. In the process, at least 5 mol of solvent can be used per mol of compound (IIIb), alternatively from 10 mol to 100 mol of solvent per mol of compound (IIIb). It can be provided that the solvent is an organic solvent. It can be provided that the solvent (both in the reaction step and in the hydrogenation step) is a non-polar organic solvent. It can be provided that the solvent is selected from n-pentane, n-hexane, n-heptane, cyclohexane, toluene, diethyl ether, dichloromethane, chloroform, tert-butyl methyl ether, acetone and tetrahydrofuran. It can be provided that the solvent is dichloromethane.


It can be provided that the reaction of the compound of the formula (IIb) with the compound of the formula (IIIb) is carried out at a temperature in a range from 0° C. to 50° C., 10° C. to 40° C., 15° C. to 30° C., 20° C. to 25° C., or 22° C. (=room temperature).


It can be provided that the reaction of the compound of the formula (IIb) with the compound of the formula (IIIb) is carried out for 5 min to 24 h, 30 min to 12 h, or 1 h to 4 h.


It can be provided that the process further comprises reacting the product obtained after the crystallization with a Grignard reagent. A Grignard reagent is a compound of the general formula R—Mg-Hal with R=acyl (for example aryl or alkyl) and Hal=halogen (for example Cl or Br). Such a compound can be prepared by reacting acyl halide with magnesium in a suitable organic solvent. Suitable organic solvents are those which can form a coordinate bond to the Mg in the R—Mg-Hal by a free electron pair. An ether (preferably a dialkyl ether such as diethyl ether or a cyclic ether such as tetrahydrofuran (THF)) is preferably used as organic solvent. Grignard reagents and their preparation and use are well known from the prior art, in particular relevant textbooks of organic chemistry.


It can be provided that a compound of the formula (Ib) with X11 to X14═Si(acyl)3 is obtained by reacting a compound of the formula (Ib) with X11 to X14=SiHal3 with a Grignard reagent of the formula R—Mg-Hal with R=acyl in THF or diethyl ether. It can be provided that a compound of the formula (Ib) with X11 to X14═Si(alkyl)3 is obtained by reacting a compound of the formula (Ib) with X11 to X14=SiHal3 with a Grignard reagent of the formula R—Mg-Hal with R=alkyl in THF or diethyl ether. It can be provided that a compound of the formula (Ib) with X11 to X14═Si(C1 to C4 alkyl)3 is obtained by reacting a compound of the formula (Ib) with X11 to X14=SiHal3 with a Grignard reagent of the formula R—Mg-Hal with R═C1 to C4 alkyl in diethyl ether. It can be provided that a compound of the formula (Ib) with X11 to X14 ═SiMe3 is obtained by reacting a compound of the formula (Ib) with X11 to X14═SiCl3 with a Grignard reagent of the formula R—Mg-Hal with R=methyl in diethyl ether.


Preparation of a Si- and Ge-Containing Solid


The object is also achieved by the use of a compound according to the formula (Ia) or the formula (Ib) described above for preparing a Si- and Ge-containing solid.


It may be provided that the Si- and Ge-containing solid is an intermetallic phase, wherein the two semimetals Si and Ge are to be regarded as metals in this context. An intermetallic phase (also intermetallic compound) is a chemical compound of two or more metals. In contrast to alloys, the intermetallic phase has lattice structures which differ from those of the constituent metals. The lattice bond of the different atom types is a mixed form of a predominantly metallic bond and smaller proportions of other types of bonds (covalent bond, ion bond), whereby these phases have particular physical and mechanical properties.


It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 300° C. or more. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 400° C. or more. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 450° C. or more. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 500° C. or more. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 550° C. or more. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 600° C. or more. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 400° C. to 1000° C. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 400° C. to 800° C. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 450° C. to 750° C. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 500° C. to 700° C. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of 550° C. to 650° C. It may be provided that the preparation of the Si- and Ge-containing solid comprises heating the compound to a temperature of about 600° C.


It may be provided that the preparation of the Si- and Ge-containing solid comprises depositing SiGe. It may be provided that the preparation of the Si- and Ge-containing solid comprises simultaneously depositing Si and Ge. It may be provided that the stoichiometric ratio of Si to Ge in the Si- and Ge-containing solid corresponds to the stoichiometric ratio of Si to Ge in the compound of the formula (Ia) or the formula (Ib). It may be provided that the stoichiometric ratio of Si to Ge in the Si- and Ge-containing solid corresponds to the stoichiometric ratio of Si to Ge in the compound of the formula (Ia) or the formula (Ib) with a deviation of 10%.


It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 10% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 5% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 3% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 2% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 1% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 0.5% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 0.1% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 0.01% by weight or less, based on the total weight of the Si- and Ge-containing solid. It may be provided that the Si- and Ge-containing solid contains further elements in an amount of 0.001% by weight or less, based on the total weight of the Si- and Ge-containing solid.


It may be provided that further elements contained in the Si- and Ge-containing solid are selected from the group consisting of carbon, oxygen, aluminum and mixtures thereof.


It may be provided that the heating of the compound of the formula (Ia) or of the formula (Ib)




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during the preparation of the Si- and Ge-containing solid is accompanied by the formation of R1—H and R2—H, or R3—H and R4—H.


The term “alkyl” as used herein refers to mono-radical of a saturated chain or branched hydrocarbon. Preferably, the alkyl group comprises 1 to 12 (about 1 to 10) carbon atoms, i.e. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 carbon atoms, preferably 1 to 8 carbon atoms, alternatively 1 to 6 or 1 to 4 carbon atoms. Exemplary alkyl groups are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, iso-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.


The term “alkenyl” as used herein refers to the mono-radical of a saturated chain or branched hydrocarbon having at least one double bond.


The term “alkynyl” as used herein refers to the mono-radical of a saturated chain or branched hydrocarbon having at least one triple bond.


The term “aryl” as used herein refers to the mono-radical of an aromatic cyclic hydrocarbon. Preferably, the aryl group contains 5 to 14 (e.g. 5, 6, 7, 8, 9, 10) carbon atoms, which may be arranged in one ring (e.g. “phenyl”=“Ph”) or in two or more fused rings (e.g. “naphthyl”). Exemplary aryl groups are, for example, cyclopentadienyl, phenyl, indenyl, naphthyl, azulenyl, fluorenyl, anthryl, and phenanthryl.


The term “cycloalkyl” as used herein refers to the cyclic, non-aromatic form of an alkyl.


The term “arylalkyl” as used herein refers to an aryl group substituted with at least one alkyl, e.g. tolueneyl.


The term “alkylaryl” as used herein refers to an alkyl group substituted with at least one aryl, e.g. 2-phenylethyl.


The term “halogen” as used herein refers to fluorine, chlorine, bromine, or iodine.





DETAILED DESCRIPTION OF THE INVENTION

The invention will be described in detail below with reference to particularly preferred embodiments and exemplary embodiments. However, the invention is not limited to these particularly preferred embodiments and exemplary embodiments, wherein individual features of the particularly preferred embodiments and exemplary embodiments together with other features or features of the preceding general disclosure of the invention can serve to realize the invention.



FIG. 1 shows the crystal structure of the compound A7.



FIG. 2 shows the crystal structure of the compound A8.





The present invention relates to the novel silylated oligogermanes of the formula (Ia)




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The present invention also relates to the novel polycyclic silicon-germanium compounds of the formula (Ib)




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Compounds of the formula (Ia) are obtainable via a novel synthesis, for example starting from diorganyldichlorogermane and hexachlorodisilane. The target compounds (Ia) can be prepared, for example, by adding tetrabutylammonium chloride and subsequent hydration with lithium aluminum hydride. These oligogermanes are distinguished by their thermolysis behavior, for example, in the deposition of pure Si and Ge, the residue obtained here consisting of pure Si and Ge in the stoichiometric ratio.


Compounds of the formula (Ib) are obtainable via a novel synthesis, for example starting from diorganyldichlorogermane and hexachlorodisilane. The target compounds (Ib) can be prepared, for example, by adding tetrabutylammonium chloride and optionally subsequent reaction with a Grignard reagent. These polycyclic silicon-germanium compounds are distinguished by their thermolysis behavior, for example, in the deposition of pure Si and Ge, the residue obtained here consisting of pure Si and Ge in the stoichiometric ratio.


General Synthesis Route for the Compounds of the Formula (Ia)


The reaction of diorganodichlorogermanes with hexachlorodisilane with addition of tetrabutylammonium chloride followed by hydrogenation with LialH4 leads to the selective formation of the silylated oligogermanes H3Si—(GeR2)n—X1 (where n=1-4; R=alkyl, aryl; X1═H, Cl, SiH3, SiCl3).




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Particularly preferred compounds which can be prepared in this way are the following compounds A1 to A8




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The compounds according to the invention can be prepared according to the following Scheme 1.




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Scheme 1 shows the reaction of diorganodichlorogermanes with hexachlorodisilane with addition of tetrabutylammonium chloride to give the trichlorosilylated oligogermanes Cl3Si—(GeR2)n—Y (B, where n=1-4; R=alkyl, aryl; Y═Cl, SiCl3). The subsequent hydrogenation with LiAlH4 leads to the selective formation of the silylated oligogermanes H3Si—(GeR2)n—Y (A, m it n=1-4; R=alkyl, aryl; Y═H, Cl, SiH3, SiCl3).




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Synthesis Examples for the Compounds of the Formula (Ia)


Synthesis of Cl3Si-Ph2Ge—SiCl3 (B1)


A solution of [nBu4N]Cl (90 mg, 0.34 mmol, 0.2 eq.), Ph2GeCl2 (500 mg, 1.70 mmol, 1 eq.), 5 ml of CH2Cl2 and Si2Cl6 (1800 mg, 6.80 mmol, 4 eq.) was stirred at room temperature overnight and then freed from all volatile constituents under reduced pressure. The orange-colored viscous residue was extracted with 6 ml of n-hexane and all volatile constituents were removed from the filtrate under reduced pressure. In this way, Cl3Si-Ph2Ge—SiCl3 (79%, 659 mg, 1.34 mmol) was obtained as a colorless, viscous liquid.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=7.57-7.52 (m, 4H), 7.44-7.35 ppm (m, 6H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=136.0 (ortho), 131.1 (para), 129.9 (meta), 129.4 ppm (ipso).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=9.7 ppm.


EA (%): Calculated for C12H10Si2Cl6Ge [495.70 g/mol]: C 29.08, H 2.03; found: C 29.51, H 2.07.


Synthesis of Cl3Si-Me2Ge—SiCl3 (B2)


[nBu4N]Cl (200 mg, 0.73 mmol, 0.2 eq.), Me2GeCl2 (500 mg, 3.63 mmol, 1 eq.), 10 ml of CH2Cl2 and Si2Cl6 (1950 mg, 7.26 mmol, 2 eq.) were stirred at room temperature for 3 hours and then all volatile constituents were removed under reduced pressure. The crude product was extracted twice with 5 ml of n-hexane each time and all volatile constituents were removed from the filtrate under reduced pressure. In this way, 370 mg of a colorless liquid were obtained. NMR spectroscopy and GC/MS confirmed the presence of a mixture of Cl3Si-Me2Ge—SiCl3 and Cl3Si-Me2Ge-Me2Ge—SiCl3.


Cl3Si-Me2Ge—SiCl3 was identified using the following signals:



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=0.79 ppm (s, 6H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=−5.2 ppm.



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=13.2 ppm.


Synthesis of Cl3Si-Ph2Ge-Ph2Ge—SiCl3 (B3)


[nBu4N]Cl (180 mg, 0.65 mmol, 0.2 eq.), Ph2GeCl2 (900 mg, 3.02 mmol, 1 eq.), 10 ml of CH2Cl2 and Si2Cl6 (1600 mg, 5.95 mmol, 2 eq.) were stirred at room temperature for 3 hours and then all volatile constituents were removed under reduced pressure. The crude product was washed dropwise with a total of 2.5 ml of CH2Cl2 in order to obtain Cl3Si-Ph2Ge-Ph2Ge—SiCl3 as a colorless solid in 88% yield (956 mg, 1.32 mmol).



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=7.62-7.56 (m, 8H), 7.54-7.38 ppm (m, 12H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=136.3 (ortho), 132.2 (ipso), 130.5 (para), 129.4 ppm (meta).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=12.4 ppm.


EA (%): Calculated for C24H20Si2Cl6Ge2 [722.55 g/mol]: C 39.90, H 2.79; found: C 40.64, H 3.02.


Synthesis of Cl3Si-Me2Ge-Me2Ge—SiCl3 (B4)


[nBu4N]Cl (800 mg, 2.91 mmol, 0.4 eq.), Me2GeCl2 (1000 mg, 7.27 mmol, 1 eq.), 20 ml of CH2Cl2 and Si2Cl6 (3900 mg, 14.54 mmol, 2 eq.) were stirred at room temperature for 24 hours and then all volatile constituents were removed under reduced pressure. The crude product was extracted four times with 5 ml of n-hexane each time and all volatile constituents were removed from the filtrate under reduced pressure. In this way, Cl3Si-Me2Ge-Me2Ge—SiCl3 (34%, 589 mg, 1.24 mmol) was obtained as a colorless liquid.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=0.72 ppm (s, 12H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=−4.3 ppm.



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=16.7 ppm.


Synthesis of Cl3Si-Ph2Ge-Ph2Ge—Cl (B5)


[nBu4N]Cl (10 mg, 0.03 mmol, 0.1 eq.), Ph2GeCl2 (100 mg, 0.34 mmol, 1 eq.), 1 ml of CD2Cl2 and Si2Cl6 (90 mg, 0.34 mmol, 1 eq.) were mixed in a glass and then half the batch was added to an NMR tube. After melting in oil pump vacuum, Cl-Ph2Ge-Ph2Ge—Cl, Cl3Si-Ph2Ge-Ph2Ge—SiCl and Cl3Si-Ph2Ge-Ph2Ge—SiCl3 were detected in the reaction solution by means of NMR spectroscopy.


Cl3Si-Ph2Ge-Ph2Ge—Cl was identified using the following signals:



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=7.80-7.00 (m, 20H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): Cl3Si-Ph2Ge-Ph2Ge—Cl: δ=136.6 (ipso), 136.1 (ortho), 134.1 (ortho), 131.8 (ipso), 131.0 (para), 130.6 (para), 129.5 (meta), 129.2 ppm (meta).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=12.1 ppm.


Synthesis of H3Si-Ph2Ge—H (A1)


The product from the synthesis of H3Si-Ph2Ge—SiH3 was stored at room temperature for 6 months. The subsequent investigation by means of NMR spectroscopy and GC/MS confirmed the formation of H3Si-Ph2Ge—H.


H3Si-Ph2Ge—H was identified using the following signals:



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=7.70-7.20 (m), 5.07 (Ge—H, q, J=3.2 Hz, 1H), 3.57 ppm (SiH3, d, J=3.2 Hz, 3H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=136.1 (ipso), 135.5 (ortho), 129.3 (para), 128.9 ppm (meta).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=−94.9 ppm (qd, 1JHSI=199.7 Hz, 2JHSI=13.3 Hz).


Synthesis of H3Si-Ph2Ge—SiH3 (A2)


Cl3Si-Ph2Ge—SiCl3 (400 mg, 0.807 mmol, 1 eq.) was dissolved in 10 ml of Et2O and LiAlH4 (93 mg, 2.42 mmol, 3 eq.) was added in portions. The solution remained clear and colorless and a gray solid precipitated. After stirring for 30 minutes, all volatile constituents were removed under reduced pressure and the residue was stirred with 8 ml of n-hexane for 16 hours. Filtration of the n-hexane solution and liberation of the extract from all volatile constituents under reduced pressure yielded H3Si-Ph2Ge—SiH3 (55%, 128 mg, 0.443 mmol) as a viscous, colorless liquid. The product was identified by means of NMR spectroscopy and GC/MS.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=7.42-7.38 (m, 4H), 7.27-7.23 (m, 6H), 3.50 ppm (s, 6H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=136.8 (ipso), 135.4 (ortho), 129.1 (para), 128.9 ppm (meta).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=−91.2 ppm (qq, 1JHSI=200 Hz, 3JHSI=3 Hz).


Synthesis of H3Si-Me2Ge—SiH3 (A3) and H3Si-Me2Ge-Me2Ge—SiH3 (A5)


50 mg of a mixture of Cl3Si-Me2Ge—SiCl3 (B2) and Cl3Si-Me2Ge-Me2Ge—SiCl3 (B4) was dissolved in 0.8 ml of Et2O in an NMR tube and an excess of LiAlH4 (15 mg, 0.4 mmol, about 3 eq.) was slowly added. 0.2 ml of the solution was taken for a GC/MS sample and diluted with a further 0.5 ml of Et2O. The remaining reaction solution was melted in the NMR tube under vacuum and measured by NMR spectroscopy. GC/MS and NMR spectroscopy confirmed the formation of H3Si-Me2Ge—SiH3 and H3Si-Me2Ge-Me2Ge—SiH3.



1H NMR (500.2 MHz, Et2O, 298 K): δ=0.93 ppm; H3Si-Me2Ge-Me2Ge-SiH3: δ=0.89 ppm.



13C{1H} NMR (125.8 MHz, Et2O, 298 K): δ=−4.0 ppm; H3Si-Me2Ge-Me2Ge-SiH3: δ=−4.8 ppm.



29Si NMR (99.4 MHz, Et2O, 298 K): δ=−90.8 ppm (qm, 1JHSI=196 Hz); H3Si-Me2Ge-Me2Ge-SiH3: δ=−94.7 ppm (qm, 1JHSI=191 Hz).


Synthesis of H3Si-Ph2Ge-Ph2Ge—SiH3 (A4)


Cl3Si-Ph2Ge-Ph2Ge—SiCl3 (200 mg, 0.280 mmol, 1 eq.) was dissolved in 6 ml of Et2O and LiAlH4 (37 mg, 0.98 mmol, 3.5 eq.) was added in portions. The solution remained clear and colorless and a gray solid precipitated. After stirring for 30 minutes, all volatile constituents were removed under reduced pressure and the residue was stirred with 8 ml of n-hexane for 16 hours. Filtration of the n-hexane solution and liberation of the extract from all volatile constituents under reduced pressure yielded H3Si-Ph2Ge-Ph2Ge—SiH3 (55%, 128 mg, 0.44 mmol) as a colorless, crystalline solid. The product was identified by means of NMR spectroscopy.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=7.44-7.39 (m, 8H), 7.38-7.27 (m, 13H), 3.60 ppm (s, 6H).



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=127.1 (ipso), 135.8 (ortho), 129.1 (para), 128.8 ppm (meta).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=−92.6 ppm (q, 1JHSI=199.6 Hz).


Synthesis of H3Si-Ph2Ge—SiCl3 (A6)


Cl3Si-Ph2Ge—SiCl3 (50 mg, 0.10 mmol, 1 eq.) in 0.5 ml of Et2O was initially charged in an NMR tube and LiAlH4 (6 mg, 0.14 mmol, 1.4 eq.) was added. A gray solid precipitated from the colorless reaction solution. 13C and 29Si NMR spectroscopy showed Cl3Si-Ph2Ge—SiCl3, H3Si-Ph2Ge—SiCl3 and H3Si-Ph2Ge—SiH3 as reaction products.


NMR signals of H3Si-Ph2Ge—SiCl3:



13C{1H} NMR (125.8 MHz, Et2O, 298 K): δ=135.7 (ortho), 132.6 (ipso), 130.4 (para), 129.7 ppm (meta).



29Si NMR (99.4 MHz, Et2O, 298 K): δ=15.7, −93.4 ppm (q, 1JHSI=207 Hz).


Synthesis of H3Si-Ph2Ge-Ph2Ge—SiCl3 (A7)


Cl3Si-Ph2Ge-Ph2Ge—SiCl3 (200 mg, 0.280 mmol, 1 eq.) in 2 ml of Et2O was initially charged and LiAlH4 (10 mg, 0.28 mmol, 1 eq.) was slowly added. The solution remained colorless and a gray solid precipitated. The solid was filtered off and the filtrate was freed from the solvent under ambient pressure. The residue was extracted with 4 ml of n-hexane and then all volatile constituents of the extract were removed under ambient pressure. 13C and 29Si NMR spectroscopy of the solid obtained confirmed the presence of the starting material Cl3Si-Ph2Ge-Ph2Ge—SiCl3, H3Si-Ph2Ge-Ph2Ge—SiCl3 and H3Si-Ph2Ge-Ph2Ge—SiH3. It was also possible to obtain the crystal structure of H3Si-Ph2Ge-Ph2Ge—SiCl3 by means of X-ray diffractometry.


NMR signals of H3Si-Ph2Ge-Ph2Ge—SiCl3:



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=136.2 (ortho), 136.0 (ortho), 135.5 (ipso), 133.6 (ipso), 130.1 (para), 129.6 (para), 129.3 (meta), 129.0 ppm (meta).



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=−90.7 ppm (q, 1JHSI=204 Hz).


Synthesis of H3Si—(Ph2Ge)4—SiH3 (A8)


An NMR tube was filled with [nBu4N]Cl (10 mg, 0.03 mmol, 0.2 eq.), Ph2GeCl2 (50 mg, 0.17 mmol, 1 eq.), 0.5 ml of CD2Cl2 and Si2Cl6 (90 mg, 0.34 mmol, 2 eq.). 13C and 29Si NMR spectroscopy of the clear, colorless solution confirmed the presence of Cl3Si-Ph2Ge-Ph2Ge—SiCl3, Cl3Si-Ph2Ge—SiCl3 and SiCl4. The NMR tube was opened and all volatile constituents were removed under ambient pressure. The residue was dissolved in a new NMR tube in 0.5 ml of Et2O and LiAlH4 (7 mg, 0.17 mmol, 1 eq.) was added. A colorless solution with a gray sediment and a fine, colorless solid was then present. 13C and 29Si NMR spectroscopy of the reaction solution gave the signals of several unknown species which could not be characterized more precisely. After opening the NMR tube and removing the volatile constituents under ambient pressure, a crystal was obtained which was identified by means of X-ray diffractometry as the tetragerman H3Si—(Ph2Ge)4—SiH3.


Synthesis Examples for the Compounds of the Formula (Ib)


Synthesis of C10H30Cl4Ge5Si9 (C1)




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[nBu4N]Cl (161 mg, 0.58 mmol, 0.2 eq.), Me2GeCl2 (500 mg, 2.88 mmol, 1 eq.), 10 ml of CH2Cl2 and Si2Cl6 (3092 mg, 11.5 mmol, 4 eq.) were stirred at room temperature for 3 hours and then all volatile constituents were removed under reduced pressure. The crude product was washed twice with 5 ml of n-hexane each time and the residue was dissolved in CH2Cl2. A colourless solid crystallized out over time. Washing with CH2Cl2 yielded C1 (4%, 32 mg, 0.025 mmol) as a colorless crystalline solid. The product was characterized by means of X-ray diffractometry (orthorhombic, Cmc21) and NMR spectroscopy.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=1.00, 0.94, 0.93 ppm.



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=2.57, 2.23, 1.97 ppm.



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=16.2, 12.1, −80.7, −83.3 ppm.


Synthesis of C8H24Cl16Ge4Si10 (C2)




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[nBu4N]Cl (161 mg, 0.58 mmol, 0.2 eq.), Me2GeCl2 (500 mg, 2.88 mmol, 1 eq.), 10 ml of CH2Cl2 and Si2Cl6 (3092 mg, 11.5 mmol, 4 eq.) were filled into a bulkhead bottle. After a few days, colorless crystals had formed which could be isolated by means of filtration. Washing with CH2Cl2 yielded C2 (18%, 163 mg, 0.13 mmol) as a colorless crystalline solid. The product was characterized by means of X-ray diffractometry (trigonal, R-3) and NMR spectroscopy.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=1.03 ppm.



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=1.59 ppm.



29Si NMR (99.4 MHZ, CD2Cl2, 298 K): δ=11.9, −80.8 ppm.


Synthesis of C22H66Cl2Ge5Si9 (C3)




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C1 (12 mg, 0.009 mmol, 1 eq.) and 0.5 ml of Et2O were filled into an NMR tube and an Et2O solution of MeMgBr (3 M, 0.1 ml, 0.30 mmol, 30 eq.) was added with ice cooling. The NMR tube was melted in under vacuum. After about two weeks at room temperature, a complete conversion could be observed by means of NMR spectroscopy. The NMR tube was then opened, the contents were transferred together with 3 ml of Et2O into a Schlenk flask and then 0.05 ml of MeOH was added with ice cooling. After stirring for 10 minutes, all volatile constituents were removed, and the residue was extracted with a total of 7 ml of n-hexane. Again, all volatile constituents were removed from the extract, whereupon C3 (82%, 8 mg, 0.008 mmol) was obtained as a colorless crystalline solid. The product was characterized by means of X-ray diffractometry (orthorhombic, Cmcm) and NMR spectroscopy.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=0.66, 0.61, 0.59, 0.35, 0.27 ppm.



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=4.06, 3.81, 3.60, 3.27, 2.92 ppm.



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=2.6, 3.5, 91.5, 97.2 ppm.


Synthesis of C20H60Cl4Ge4Si10 (C4)




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C2 (20 mg, 0.015 mmol, 1 eq.) and 0.5 ml of Et2O were filled into an NMR tube and an Et2O solution of MeMgBr (3 M, 0.2 ml, 0.60 mmol, 40 eq.) was added with ice cooling. The NMR tube was melted in under vacuum. After heating for 14 h at 60° C., a complete conversion could be observed by means of NMR spectroscopy. The further purification was then carried out analogously to C3.


Finally, C4 (89%, 16 mg, 0.016 mmol) was obtained as a colorless crystalline solid. The product was characterized by means of X-ray diffractometry (orthorhombic, Pbca) and NMR spectroscopy.



1H NMR (500.2 MHz, CD2Cl2, 298 K): δ=0.70, 0.37 ppm.



13C{1H} NMR (125.8 MHz, CD2Cl2, 298 K): δ=3.7, 2.5 ppm.



29Si NMR (99.4 MHz, CD2Cl2, 298 K): δ=−1.8, −91.6 ppm.


Preparation of Si- and Ge-Containing Solids


Si- and Ge-Containing Solids can be prepared starting from the compounds according to the invention, for example according to the following reaction scheme.




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Deposition of SiGe at 600° C.


H3Si-Ph2Ge-Ph2Ge—SiH3 (13 mg, 0.025 mmol) was weighed into a crucible and a thermogravimetric analysis (TGA) was carried out. For this purpose, the mixture was heated to 600° C. under an argon atmosphere at a rate of 10 K/min, this temperature was maintained for 5 minutes and the sample was then cooled again to room temperature at the same rate. The residue obtained, a brownish powder, was examined by means of EDX. For this purpose, some of the sample was applied to a support and coated with gold for better measurement accuracy. In addition to silicon and germanium, the subsequent measurement showed only gold, as well as small amounts of carbon, oxygen and aluminum. The evaluation of the data of two analyzed regions showed a silicon-germanium ratio of 1.0:1.0 or 1.0:1.1.


The features of the invention disclosed in the above description and in the claims can be essential both individually and in any combination for the realization of the invention in its various embodiments.

Claims
  • 1. A compound of the formula (Ia) or (Ib)
  • 2. A compound according to claim 1, wherein n is an integer from 1 to 4.
  • 3. A compound according to claim 1, wherein R1 and R2 are independently of each other selected from the group consisting of C1 to C20 alkyl and C6 to C20 aryl.
  • 4. A compound according to claim 1, wherein R1 and R2 are independently of each other phenyl or methyl.
  • 5. A compound according to claim 1, wherein R1 and R2 are the same.
  • 6. A compound according to claim 1, wherein X1 is selected from the group consisting of H, SiH3, Cl and SiCl3.
  • 7. A compound according to claim 1, wherein at least three of E1 to E6 are Ge and the remaining of E1 to E6 are Si.
  • 8. A compound according to claim 1, wherein R3 to R14 are independently of each other selected from the group consisting of C1 to C20 alkyl and halogen.
  • 9. A compound according to claim 1, wherein R3 to R14 are independently of each other selected from the group consisting of methyl and Cl.
  • 10. A compound according to claim 1, wherein X11 to X14 are independently selected from the group consisting of H, SiH3, Si(C1 to C4 alkyl)3, Cl and SiCl3.
  • 11. A compound according to claim 1, wherein X11 to X14 are independently selected from the group consisting of SiCl3 and Si(CH3)3.
  • 12. Process for preparing a compound of the formula (Ia) according to claim 1 comprising reacting a compound of the formula (IIa)
  • 13. The process according to claim 12, wherein the reaction of the compound of the formula (IIa) with the compound of the formula (IIIa) is carried out in the presence of a catalyst.
  • 14. Process for preparing a compound of the formula (Ib) according to claim 1 comprising reacting a compound of the formula (IIb)
  • 15. The process according to claim 14, wherein the reaction of the compound of the formula (IIb) with the compound of the formula (IIIb) is carried out in the presence of a catalyst.
  • 16. The process according to claim 14, further comprising reacting the product obtained after the crystallization with a Grignard reagent.
  • 17. Process for preparation of a Si- and Ge-containing solid, comprising heating the compound of the formula (Ia) or the compound of the formula (Ib) according to claim 1.
  • 18. The process according to claim 17, wherein the preparation comprises heating the compound to a temperature of 300° C. or more.
Priority Claims (2)
Number Date Country Kind
10 2020 114 994.8 Jun 2020 DE national
10 2020 131 425.6 Nov 2020 DE national
PCT Information
Filing Document Filing Date Country Kind
PCT/DE2021/100470 6/1/2021 WO