Method of preparing an organosilicon compound

Abstract

The present disclosure provides a method of preparing an organosilicon compound. The method includes combining (A) a hydridosilane, (B) an arene compound, and (C) a catalyst including a boron cluster, thereby preparing a reaction mixture including the organosilicon compound. The hydridosilane (A) has the formula HSiQ3, where each Q is an individually selected halogen atom. The organosilicon compound has the formula RSiQ3, where R is an aryl group, and each Q is independently selected and defined above. The present disclosure further provides a reaction product prepared via the method.

Description

METHOD OF PREPARING AN ORGANOSILICON COMPOUNDCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and all advantages of U. S. Provisional Patent Application No. 63 / 716,231 filed on 04 November 2024, and U. S. Provisional Patent Application No. 63 / 784,600 filed on 07 April 2025, the content of which is incorporated herein by reference.FIELD OF THE INVENTION

[0002] The present disclosure relates generally to a method of preparing an organosilicon compound, and more specifically, a method of preparing an organosilicon compound by combining a hydridosilane, an arene compound, and a catalyst comprising a boron cluster, as well as a reaction product comprising the organosilicon compound using the same.DESCRIPTION OF THE RELATED ART

[0003] Chlorosilanes are commonly used in polymer chemistry, especially siloxane chemistry, as starting materials, e.g., to synthesize resins, or as reactants / reagents. Various chlorosilanes, such as phenyltrichlorosilane (PhSiCl3), are also utilized as intermediates in various siloxane chemistries.

[0004] In conventional methods, phenyltrichlorosilane is manufactured via various techniques or mechanisms. For example, phenyltrichlorosilane can be prepared via a Grignard reaction involving phenylmagnesium bromide or chloride as a Grignard reagent. Alternatively, phenyltrichlorosilane can be prepared by the Pseudo Friedel-Crafts reaction using BCI3 as a catalyst. However, regardless of the chemistry utilized to prepare phenyltrichlorosilane, conventional processes are very high cost and generate significant volumes of waste.BRIEF SUMMARY

[0005] The present disclosure provides a method of preparing an organosilicon compound. The method comprises combining (A) a hydridosilane, (B) an arene compound, and (C) a catalyst. The (C) catalyst comprises a boron cluster and is capable of coupling the arene compound (B) to a silicon atom of the hydridosilane (A), thereby preparing a reaction mixture comprising the organosilicon compound. The hydridosilane (A) has the formula HSiQ3, each Q is an individually selected halogen atom. The organosilicon compound has the formula RSiQ3-Each R is an aryl group, and each Q is independently selected and defined above.

[0006] The present disclosure further provides a reaction product comprising the organosilicon compound prepared in accordance with the method.DETAILED DESCRIPTION

[0007] A method of preparing an organosilicon compound is disclosed. The organosilicon compound can be utilized in myriad end use applications and can be selectively prepared via the inventive method in excellent yields.

[0008] The method comprises combining (A) a hydridosilane, (B) an arene compound, and (C) a catalyst comprising a boron cluster and capable of coupling the arene compound (B) to a silicon atom of the hydridosilane (A), thereby preparing a reaction mixture comprising the organosilicon compound. The hydridosilane (A), the arene compound (B), and the catalyst (C) can be combined in any order of addition, optionally via masterbatches, and optionally under shear or mixing.

[0009] The hydridosilane (A) has the formula HSiQ3, where each Q is an individually selected halogen atom. Each Q is independently selected from fluorine (F), chlorine (Cl), bromine (Br), iodine (I). In certain embodiments, each Q is independently fluorine (F), chlorine (Cl), or bromine (Br). In specific embodiments, each Q is Cl. When each Q is Cl, the hydridosilane (A) is trichlorosilane (HSiCIs).

[0010] The hydridosilane (A) can comprise a single hydridosilane or a blend of two or more hydridosilanes that differ from one another based on the selection of Q.

[0011] The arene compound (B) is not limited and can be any cyclically conjugated hydrocarbon group. For purposes of this disclosure, the arene compound (B) can be any cyclic compound that is considered aromatic by satisfying Huckel's rule. Typically, the arene compound (B) is non-electron enriched.

[0012] In certain embodiments, the arene compound (B) is further defined as a benzoid compound, i.e., the arene compound comprises a benzene ring or derivative thereof. Typically, the arene compound (B) is a pure hydrocarbon and does not include any heteroatom (e.g., oxygen, nitrogen, or sulfur) replacing at least one methine or vinylene group, i.e., in certain embodiments, the arene compound (B) consists essentially of, or consists of, carbon and hydrogen atoms. The arene compound (B) can comprise or include a single aromatic ring or moiety (i.e., the arene compound (B) may comprise or be a monocyclic moiety or compound), or the arene compound (B) can comprise or be a polycyclic aromatic moiety or compound. Typically, the arene compound (B) is monocyclic. The arene compound (B) comprises, in particular embodiments, from 3 to 20, alternatively from 3 to 18, alternatively from 3 to 16, alternatively from 3 to 14, alternatively from 3 to 12, alternatively from 3 to 10, alternatively from 4 to 8, alternatively from 5 to 7, alternatively 6 or 7, carbon atoms. In some embodiments, the arene compound (B) is selected from benzene, xylene, and toluene. In specific embodiments, the arene compound (B) comprises, alternatively consists of, benzene.

[0013] In certain embodiments, the arene compound (B) may be substituted with one or more other hydrocarbon groups. For example, one of the hydrogen atoms of the arene compound (B) may be replaced or substituted with another hydrocarbon group, e.g., a hydrogen atom may be replaced with a hydrocarbyl group. By way of example, substituted versions of benzene suitable for the arene compound (B) include toluene, ethylbenzene, p-xylene, m-xylene,mesitylene, durene, 2-phenylhexane, etc. Typically, the arene compound (B) is free from substitution other than hydrocarbon groups, i.e., in certain embodiments, the arene compound is free from substitution based on groups other than hydrocarbons. In such embodiments, the arene compound (B) is not, for example, aniline, nitrobenzene, benzoic acid, etc., all of which include non-hydrocarbon substitution of a benzene moiety.

[0014] In certain embodiments, the arene compound (B) is utilized in a molar excess relative to silicon-bonded hydrogen atom of the hydridosilane (A). For example, because the hydridosilane (A) includes one silicon-bonded hydrogen atom, in such embodiments, the arene compound (B) is typically used in a molar ratio of from greater than 1:1 to 100:1, alternatively from greater than 1: 1 to 80: 1, alternatively from greater than 1: 1 to 60: 1, alternatively from greater than 1:1 to 40: 1, alternatively from greater than 1:1 to 20: 1, alternatively from greater than 1: 1 to 10:1, relative to the hydridosilane (A). In other embodiments, however, the hydridosilane (A) is utilized in a molar excess relative to the arene compound (B). In such embodiments, the molar ratios above apply in inverted form, i.e., the ratios above apply as the ratio of the hydridosilane (A) to the arene compound (B).

[0015] The (C) catalyst comprises a boron cluster and is capable of coupling the arene compound (B) to a silicon atom of the hydridosilane (A). The catalyst (C) is not limited so long as the catalyst comprises the boron cluster and is capable of coupling the arene compound (B) to a silicon atom of the hydridosilane (A) to give the organosilicon compound. The catalyst (C) may be formed in situ in the presence of the hydridosilane (A) and / or the arene compound (B). For example, the composition may utilize a pre-catalyst, which converts to a catalytically active form in situ to give the catalyst (C). In such embodiments, the pre-catalyst may be any suitable precatalyst that forms the catalytically active form of the catalyst (C) in situ.

[0016] In certain embodiments, the catalyst (C) comprises a salt comprising one dianion having a charge of -2 and two cations, wherein the one dianion comprises the boron cluster.

[0017] In specific embodiments, the one dianion has the formula (BaX^Y^-, where subscript a is 10 or 12, subscripts b and c are each independently selected integers greater than zero and b+c=a, wherein X and Y may be the same or different, and each X and each Y is independently selected from -SiR^ groups, where each R^ is independently an alkyl group or a halogen atom; halogen atoms; H; hydrocarbyl groups; with the proviso that at least one X and / or at least one Y is a halogen atom. In these embodiments, X and Y, and thus the dianion or boron cluster, are free from oxygen atoms.

[0018] The halogen atoms represented by X and Y can be fluorine (F), chlorine (Cl), bromine (Br), iodine (I). In certain embodiments, when X and / or Y is a halogen atom, the halogen atom is Br, Cl, or F. In yet other embodiments, when X and / or Y is a halogen atom, the halogenatom is Cl or F. In specific embodiments, when X and / or Y is a halogen atom, the halogen atom is Cl.

[0019] In one embodiment, at least one X and / or Y is an -SiR^ groups, where each R^ is independently an alkyl group or a halogen atom. When each R^ is methyl, the -SiR^ group is a trimethylsilyl group. When two of R”* are methyl and the other is chlorine, the -SiR^ group is a dimethylchlorosilyl group. When all of R^ are chlorine, the -SiR^ group is a trichlorosilyl group.

[0020] In one embodiment, at least one X and / or Y is a hydrocarbyl group, which are independently selected when more than one X and Y, individually or collectively, is a hydrocarbyl group. Suitable hydrocarbyl groups may independently be linear, branched, cyclic, or combinations thereof. Cyclic hydrocarbyl groups encompass aryl groups as well as saturated or non-conjugated cyclic groups. Cyclic hydrocarbyl groups may be monocyclic or polycyclic. Linear and branched hydrocarbyl groups may independently be saturated or unsaturated. One example of a combination of a linear and cyclic hydrocarbyl group is an alkyl substituted aryl group. By “substituted,” it is meant that one or more hydrogen atoms may be replaced with atoms other than hydrogen (e.g. a halogen atom, such as chlorine, fluorine, bromine, etc.) or groups other than hydrogen. Suitable alkyl groups are exemplified by, but not limited to, methyl, ethyl, propyl (e.g. isopropyl and / or n-propyl), butyl (e.g. isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g. isopentyl, neopentyl, and / or tert-pentyl), hexyl, as well as branched saturated hydrocarbon groups of 6 carbon atoms. Suitable aryl groups are exemplified by, but not limited to, phenyl, tolyl, xylyl, naphthyl, benzyl, and dimethylphenyl. Suitable alkenyl groups include vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, pentenyl, heptenyl, hexenyl, and cyclohexenyl groups. Suitable monovalent halogenated hydrocarbon groups include, but are not limited to, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms. Suitable halogenated alkyl groups are exemplified by, but not limited to, the alkyl groups described above where one or more hydrogen atoms is replaced with a halogen atom, such as F or Cl. For example, fluoromethyl, 2-fluoropropyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 4, 4, 4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, and 8,8,8,7,7-pentafluorooctyl, 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4-difluoro-5-methylcycloheptyl, chloromethyl, chloropropyl, 2-dichlorocyclopropyl, and 2,3-dichlorocyclopentyl are examples of suitable halogenated alkyl groups. Suitable halogenated aryl groups are exemplified by, but not limited to, the aryl groups described above where one or more hydrogen atoms is replaced with a halogen atom, such as F or Cl. For example, chloroaryl and fluoroaryl are suitable halogenated aryl groups.

[0021] In specific embodiments when at least one X and / or at least one Y is a hydrocarbyl group, the hydrocarbyl group is unsubstituted, and is selected from aliphatic hydrocarbon groupsand aromatic hydrocarbyl groups. In more specific embodiments, the hydrocarbyl group is selected from alkyl groups and aryl groups.

[0022] Examples of suitable alkyl groups for X, Y, and R^ include methyl, ethyl, propyl (e.g. isopropyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g. isopentyl, neopentyl, and / or tert-pentyl), hexyl, hexadecyl, and octadecyl, as well as branched saturated hydrocarbon groups having from 6 to 8 carbon atoms. Examples of suitable non-conjugated cyclic groups (e.g. cycloalkyl groups) include cyclobutyl, cyclohexyl, and cycloheptyl groups.

[0023] In one embodiment, subscript a is 10. In another embodiment, subscript a is 12. In one embodiment when subscript a is 10, at least two, alternatively at least three, alternatively at least four, alternatively at least five, alternatively at least six, alternatively at least seven, alternatively at least eight, alternatively at least nine, alternatively all 10 of X and Y as indicated by subscripts b and c, respectively, are halogen atoms. In one embodiment when subscript a is 12, at least two, alternatively at least three, alternatively at least four, alternatively at least five, alternatively at least six, alternatively at least seven, alternatively at least eight, alternatively at least nine, alternatively at least 10, alternatively at least 11, alternatively all 12 of X and Y as indicated by subscripts b and c, respectively, are halogen atoms.

[0024] Typically, the two cations of the salt of the catalyst (C) are independently selected Brgnsted or Lewis acids. In one embodiment, each of the two cations of the catalyst (C) are independently selected Brsnsted acids. In another embodiment, each of the two cations of the catalyst (C) are independently selected Lewis acids. In yet another embodiment, one cation is a Br nsted acid, and the other is a Lewis acid.

[0025] In one embodiment, at least one cation comprises, alternatively both cations comprise, an independently selected Brensted acid. When at least one cation comprises a Br0nsted acid, the cation may comprise or be a proton (H+), which may optionally be associated with a molecule. When the cation is associated with the molecule, the molecule is typically free from oxygen atoms, and may be or comprise, for example, a hydrocarbon or a silane compound.

[0026] In one embodiment, at least one cation comprises, alternatively both cations comprise, a proton associated with a hydrocarbon and / or a silane compound. Specific examples of suitable hydrocarbons include those described above for X and Y, but in the form of hydrocarbon molecules rather than hydrocarbon substituents (i.e., not in monovalent form). By way of example, a hexenyl group described above for X or Y would be suitable as the hydrocarbon as the molecule as hexene, i.e., not in monovalent form. Any of the groups above for X or Y could be rewritten as H-X or H-Y for the hydrocarbon.

[0027] In specific embodiments when at least one cation comprises, alternatively both cations comprise, a proton associated with a hydrocarbon, the hydrocarbon comprises at least one unsaturated moiety, which may be aliphatic or aromatic. For example, when the hydrocarboncomprises at least one unsaturated moiety, the hydrocarbon may be an alkene, an alkyne, an arene, etc. In one embodiment, the proton can be associated with an arene to give an arenium cation.

[0028] In one embodiment, at least one cation comprises, alternatively both cations comprise, an independently selected Lewis acid.

[0029] In one embodiment, at least one cation comprises a Lewis acid, and the Lewis acid comprises a silylium cation or a carbocation. Specific examples of suitable carbocations include areniums, benzyl, t-butyl, trityl, CH3+, and other tertiary hydrocarbon cations. One specific example of a suitable arenium is benzenium. One of skill in the art readily understands other suitable carbocations based on aromatic and aliphatic hydrocarbons.

[0030] In specific embodiments when at least one cation comprises a Lewis acid, and the Lewis acid comprises a silylium cation, the silylium cation has the formula (R2)3Si+, where each R2is independently selected from H, a substituted or unsubstituted hydrocarbyl group, and a halogen atom. Examples of substituted and unsubstituted hydrocarbyl groups as well as halogen atoms are described above. In specific embodiments, each R2is an independently selected alkyl group. In other embodiments, at least one R2is a halogen atom, and the remaining R2are alkyl groups.

[0031] In further specific embodiments when at least one cation comprises a Lewis acid, and the Lewis acid comprises a silylium cation, the silylium cation is associated with a substituted or unsubstituted arene, a silane compound or a hydrocarbon. Arene can optionally be substituted with one or more alkyl groups.

[0032] In other embodiments, at least one cation comprises a Lewis acid, and the Lewis acid comprises a carbocation.

[0033] Any of the hydridosilane (A), the arene compound (B), and the catalyst (C) may also be disposed in a vehicle, e.g. a solvent which solubilizes the respective component, alternatively a vehicle which merely carries or disperses, but does not solubilize, the respective component. Such vehicles are known in the art. Alternatively, the hydridosilane (A), the arene compound (B), and the catalyst (C) may be combined neat. Further still, the hydridosilane (A), the arene compound (B), and the catalyst (C) may also be utilized neat but then may be combined with other components, e.g. a vehicle or solvent, when preparing the organosilicon compound with components (A) and (B).

[0034] Suitable vehicles include conventional organic solvents. Examples of organic solvents include: aliphatic hydrocarbons, such as heptane, hexane, octane, etc.;; and other organic compounds that present as liquid / fluid at typical reaction temperatures, such as white spirits, mineral spirits, naphtha, n-methylpyrrolidone; and the like, as well as derivatives, modifications, and combinations thereof.

[0035] The vehicle, if utilized, is different from components (A) and (B) and does not react in the coupling rection of component (B) to component (A) to give the organosilicon compound (or is otherwise removed prior to the reaction). Alternatively, in lieu of a discrete vehicle, an excess amount of the arene compound (B) can be utilized, which can also serve as a vehicle but is not considered as such for purposes of this disclosure in view of component (B).

[0036] As introduced above, in various embodiments, the method comprises combining the hydridosilane (A), the arene compound (B), and a pre-catalyst (C1) different from the catalyst (C), and wherein the catalyst (C) is formed in situ in the presence of the hydridosilane (A) and the arene compound.

[0037] Exemplary examples of the pre-catalyst (C1) include [Et3Si]2[B-|2£='H 2]> H[Et3Si][B12Br12], H[Et3Si][B12CI12], [Et3Si]2[B12Br12], [Et3Si]2[B12l12], [Et3Si]2[B12CI-| -|Br], [Et3Si]2[B10CI10], [Et3Si]2[B10Br10], [Et3Si]2[B12F12], [C6H7]2[Bi2Cli2], H[CeH7][B-|2CI -|2], and combinations thereof. One of skill in the art readily appreciates how, in any of the examples above, any chlorine atom may be replaced with another halogen atom, and different combinations are contemplated in view of the selections of X and Y and subscripts a and b in the catalyst (C) and corresponding pre-catalyst (C1).

[0038] The examples of the pre-catalyst (C1) above are non-hydrated (or “dry”) species. The dry species can be synthesized directly, or synthesized by removing water from hydrated (or “wet”) species. Particular examples of hydrated or wet species that may be utilized to prepare the pre-catalyst (C1) upon water removal include (H)2[B-|2CI-|2]-6(H2O), (H)2[B-|2Br-|2]-6(H2O), (H)2[B12I12]-6(H2O), (H^B^CIuB -e^O), (H)2[B10CI10]-6(H2O), (H)2[B10Br10]-6(H2O), (H)2[BI2CII I(OH)]-6(H2O), (H)2[B12F12]-6(H2O), (H)2[B12CI9(OH)3]-6(H2O), H[Et3Si][B-|2CI9(OH)3] -6(H2O), and any of the species above for the pre-catalyst (C1) while also including water molecule association. Generally, if wet species are utilized, water is removed when preparing the pre-catalyst (C1), and the pre-catalyst (C1) itself is typically already in dried form.

[0039] In specific embodiments, the pre-catalyst (C1) comprises the hydronium salt of a boron cluster (a dianionic boron cluster). As described above, as one exemplary example, the counterion to the dianionic boron cluster can simply be two protons (H+). The boron cluster is extremely stable, and non-coordinating. Because the boron cluster is substantially noncoordinating, the associated proton or counterion is strongly acidic. Because the proton or counterion is strongly acidic, the proton will interact very strongly with water molecules. Typically, the pre-catalyst (C1) in hydrated form cannot be completely dried to become free of water by traditional means (e.g., heating under vacuum). Generally, even after drying excess water under vacuum, from two to six or more water molecules may remain associated with the boron cluster.The representations below show the same exemplary species of the pre-catalyst that is hydrated in detailed representation form, ionic representation form, and simplified representation form. Without wishing to be bound by theory, it is to be understood that despite the representation, the negative charge is understood to be delocalized across the boron cluster and as such the proton and corresponding associated protons are also understood not to be localized.

[0040] In the method of the subject disclosure, the non-hydrated versions of the precatalyst (C1) may be utilized. As described below, the number of water molecules shown is representative and may vary. The hydrated forms of the pre-catalyst (C1) can be converted to the dry or non-hydrated forms via the methods described herein and in U. S. Provisional Patent Application No. 63 / 784,583 filed on 07 April 2025 which is incorporated by reference herein. Further still, the catalyst (C) can be formed in situ, or synthesized prior to use, from other routes not reliant on the pre-catalyst (C1). In specific embodiments, the pre-catalyst (C1) is free of water molecules.

[0041] By way of example, because the cation, e.g., the proton, associated with the boron cluster is strongly acidic, the proton may react with a hydridic Si-H bond. The boron cluster will “dry” in-situ through reaction of the Si-H material with the acidic water, forming a by-product disiloxane. More specifically, the proton may react with a hydridic Si-H bond to make silylium cation and H2. Two silylium cations can then react with water to form a disiloxane, regenerating two protons. As the water molecules are subsequently removed, the proton becomes less stabilized by the coordination of water and thus becomes more acidic and thus more reactive. This reaction cascade continues until all the protons are reacted and the silylium cation remains as counterion. This is summarized below (where R is simply generic):Alternatively or in addition, the boron cluster can by “dried” in situ via a reaction with a chlorosilane, where silylium and HCI gas are prepared by drying rather than silylium and H2 gas.

[0042] Hence the hydrated or acidic form of the boron cluster can be converted to a silylium salt. In both the hydrated and silylium salt structures, the counterion is at most only very weakly coordinated to the boron cluster and these compounds should be seen as mostly ionic.

[0043] In certain embodiments, the catalyst (C), whether used discretely or formed in situ, comprises a halosilylium cation, typically a chlorosilylium cation. The halosilylium cation is cationic and associated with the boron cluster, which is anionic and is the counterion.

[0044] One example of the reaction mechanism for coupling the arene compound (B) to the hydridosilane (A) is below (where Me indicates methyl, and Ph indicates phenyl):

[0045] In this specific example, the arene compound (B) is benzene, and the halosilylium species is [SiCl3]+as a result of the hydridosilane (A) being HSiCl3- The halosilylium binds to benzene, breaking the aromaticity to form species D’ transiently. This species D’ can be viewed as benzene bearing a silylium cation, but also as a silylated benzene that has been protonated. A protonated benzene is highly Bronsted acidic, and can thus react with a hydridic Si-H bond to generate hydrogen gas as a byproduct and regenerate the silylium catalyst (and regain the aromaticity), closing the catalytic cycle. As a result, the catalyst (C) itself is not wholly inert during the reaction, but catalyzes more of a cascade reaction where the catalyst is regenerated when the product is formed.

[0046] Boron clusters are extremely stable, and will not be decomposed by the silylium cation (or group). In addition, boron clusters are substantially non-coordinating, thus they do not significantly quench the Lewis acidity of the silylium cation. This key combination of a highly Lewis acidic “free” silylium cation and a highly stable anionic boron cluster is what makes catalytic activity of the catalyst (C) possible.

[0047] The catalyst (C) (or the pre-catalyst (C1)) is utilized in a catalytic amount. The catalytic amount can be readily determined by one of skill in the art. In certain embodiments, the catalytic amount of the catalyst (C) (or the pre-catalyst (C1)) is from greater than 0 to 10, alternatively from greater than 0 to 9, alternatively from greater than 0 to 8, alternatively fromgreater than 0 to 7, alternatively from greater than 0 to 6, alternatively from greater than 0 to 5, alternatively from greater than 0 to 4, alternatively from greater than 0 to 3, alternatively from greater than 0 to 2, alternatively from greater than 0 to 1, alternatively from greater than 0 to 0.9, alternatively from greater than 0 to 0.8, alternatively from greater than 0 to 0.7, alternatively from greater than 0 to 0.6, alternatively from 0 to 0.5, weight percent based on the combined weights of components (A) and (B).

[0048] The organosilicon compound is prepared by reacting and coupling the arene compound (B) to the hydridosilane (A) in the presence of the catalyst (C). The reaction is typically carried out at an elevated temperature that is greater than room temperature. In certain embodiments, the elevated temperature is from greater than room temperature to 250, alternatively from 50 to 250, alternatively from 75 to 225, alternatively from 100 to 200, alternatively from 120 to 180, °C. In these or other embodiments, the reaction is carried out at an elevated pressure greater than atmospheric pressure. In certain embodiments, the elevated pressure is from greater than atmospheric pressure to 5,000 kPa. The elevated pressure may be a function of hydrogen gas generation from the reaction in a sealed reactor, vapor pressures of the reactants, intermediates, and products, the presence or absence of any optional vehicles, and / or inert gas pressure., etc.

[0049] The structure of the organosilicon compound formed via the method is a function of the particular arene compound (B) utilized. Typically, the arene compound (B) is coupled to the hydridosilane (A) via replacement of the silicon-bonded hydrogen atom of the hydridosilane (A), and thus the arene compound (B) is converted to a silicon-bonded substituent in the organosilicon compound.

[0050] The organosilicon compound has the formula RSiQ3, where R is an aryl group, and each Q is independently selected and defined above. R is formed from the arene compound (B) and thus its structure is a function of the arene compound (B), and whether the arene compound (B) comprises a blend of different compounds, in which case the organosilicon compound may be present in a reaction product as a blend of different species. The organosilicon compound is typically prepared in the reaction product. The reaction product may include the organosilicon compound and other species of organosilicon compounds that are not the target species. For example, it is possible that there could be rearrangement of other silicon-bonded groups in certain byproducts produced along with the organosilicon compound, which are not the target species. As but one example, there may be a byproduct present in the reaction product other than the organosilicon compound and having the general formula R2SiQ2, where each R and each Q is independently selected and defined above.

[0051] In certain embodiments, the method further comprises isolating the organosilicon compound from the reaction product.

[0052] The following examples, illustrating embodiments of this disclosure, are intended to illustrate and not to limit the invention. Unless otherwise noted, all reactions are carried out under air, and all solvents, substrates, and reagents are purchased or otherwise obtained from various commercial suppliers (e.g. Strem Chemicals, Sigma-Aldrich, Fisher Chemical) and utilized as received.

[0053] A brief summary is provided in T able 1 below, setting forth information as to certain abbreviations, shorthand notations, and components utilized in the Examples, as well as the sources. In the Tables below, “C” prior to identification of each Component (C) indicates a Comparative Component (C).

[0054] In each of the Examples, the catalyst (C) is prepared in situ from a pre-catalyst. Thus, each component (C) is referred to below as a Pre-Catalyst, with the corresponding catalyst being prepared in situ in each Practical Example.

[0055] Table 1: Materials Utilized and SourcesSynthesis Examples

[0056] Synthesis Example 1: [Et₃Si]₂[B₁₂Cl₁₂]

[0057] In an argon-filled glovebox, to (H)₂[B₁₂Cl₁₂]·6(H₂O) (165.7 mg, 0.25 mmol) in a 40 mL scintillation vial with no cap or stir bar was added in a single portion an excess oftriethylsilane (1.45 g, 12.45 mmol, 50.0 equiv) along with toluene (1.0 mL). The reaction mixture was heated at 80 °C for 4 h resulting in vigorous evolution of gas. Once the bubbling had stopped and an oil phase had formed at the bottom of the reaction mixture, the vial was taken off the heating plate and allowed to cool to room temperature, then placed in a -35 °C freezer for 3 days. After this time, a white solid had precipitated. The white solid was filtered and washed with hexanes (3 x 3 mL) and the solid was dried under vacuum yielding 161 mg of a white powder (yield = 82%). The identity of the target compound was confirmed by X-ray crystallography after re-crystallization from benzene. A small amount of the solid (20 mg) was heated at 70 °C in benzene-d6 and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et₃Si·C₆D₆]₂[B₁₂Cl₁₂] ■

[0058] Synthesis Example 2: [Et₃Si]₂[B₁₂Br₁₂]

[0059] In an argon-filled glovebox, to (H)2[B-|2Bri2]’6(H2O) (300 mg, 0.25 mmol, 1.0 equiv) in a 40 mL scintillation vial with no cap or stir bar was added in a single portion an excess of triethylsilane (1.17 g, 10.06 mmol, 40.0 equiv) along with toluene (2 mL). The reaction mixture was heated at 60 °C for 6 h. Once the bubbling had stopped and the solids had dissolved, the sample was allowed to cool to room temperature, then placed in a -35 °C freezer for 5 days. During this time a solid precipitated. The solids were filtered and washed with hexanes (3 x 3 mL) and dried under vacuum yielding 289 mg of an off-white powder (yield = 87%). A small amount of the solid (20 mg) was heated at 70 °C in benzene-dg and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et₃Si·C₆D₆]₂[B₁₂Br₁₂]

[0060] Synthesis Example 3: [Et₃Si]₂[B₁₂I₁₂]

[0061] In an argon-filled glovebox, to (H)₂[B₁₂I₁₂]·6(H₂O) (303 mg, 0.17 mmol, 1.0 equiv) in a 40 mL scintillation vial with no cap or stir bar was added in a single portion triethylsilane (400 mg, 3.44 mmol, 30.0 equiv) and benzene (2 mL). The reaction mixture was placed on a heating block at 60 °C. At this point the solids were insoluble and the solution had a pinkish tint. After about 5 min, gas evolution was noted, and the reaction mixture was left at that temperature. As the bubbling intensified, the solid appeared to be white and the solution was colorless. After 1 h at 60 °C, the reaction mixture was heated to 80 °C and held at that temperature for 1 h. After this time, no further gas evolution was noted. Toluene (2 mL) was added to the reaction mixture and it was heated to 100 °C and held at that temperature for 1 h. The supernatant was removed and the solids were dried under vacuum yielding 270 mg (0.143 mmol, 84% yield) of [Et₃Si]₂[B₁₂I₁₂] as a tan solid.

[0062] Synthesis Example 4: [Et₃Si]₂[B₁₂Cl₁₁Br],

[0063] In an argon-filled glovebox, to (H)₂[B₁₂Cl₁₁Br]·6(H₂O) (400 mg, 0.56 mmol, 1.0 equiv) in a 40 mL scintillation vial with no cap or stir bar was added in a single portion triethylsilane(1.3 g, 11.27 mmol, 20.0 equiv) and toluene (5 mL). The reaction mixture was heated at 50 °C for 1 h, and vigorous bubbling was observed. The vial was removed from the heat and allowed to react at room temperature for 2 h. After ca. 2 h, bubbling had subsided, and a separate phase had formed at the bottom of the vial. The sample was placed on a heating plate at 100 °C for 15 min, and then allowed to stand at room temperature for 4 days. During this time a brownish solid had formed. The supernatant was removed, and the solid was stirred with heptane at room temperature for 24 h. The heptane was removed, and the solid was dried, yielding [Et₃Si]₂[B₁₂Cl₁₁Br] (390 mg, 84% yield). A small amount of the solid (20 mg) was heated at 70 °C in benzene-dg and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et₃Si·C₆D₆]₂[B₁₂Cl₁₁Br]. A small amount of the solid (20 mg) was also fully dissolved in 80 °C benzene, and allowed to cool to room temperature, leading to growth of crystals of [Et₃Si]₂[B₁₂Cl₁₁Br] that were suitable for single-crystal X-ray diffraction.

[0064] Synthesis Example 5: [Et₃Si]₂[B₁₀Cl₁₀]

[0065] In an argon-filled glovebox, (H)2[B-| QCI -| Q] ’6(H2O) (325 mg, 0.57 mmol, 1.0 equiv) was loaded into a 30 mL vial, followed by toluene (9.9 g). Triethylsilane (2.45 g, 21.1 mmol, 37.0 equiv) was added, and the vial was placed on a hot plate (no stir bar, no cap). No bubbling was observed. The temperature was slowly increased to 100 °C while monitoring the mixture for gas generation. After 2 hours, the vial was removed from the heating block. The hot solution was added by pipette to another vial loaded with heptane (9.0 g). Immediately the mixture turned cloudy white. It slowly became more translucent, and white crystals started forming. The mixture was left overnight to cool. Liquid was siphoned from the vial via pipette and the solid was dried under vacuum. White crystalline solid remained. The target [Et₃Si]₂[B₁₀Cl₁₀] was obtained as a white crystalline solid (312 mg, 79% yield). A small amount of the solid (20 mg) was heated at 70 °C in benzene-dg and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et₃Si·C₆D₆]₂[B₁₀Cl₁₀]

[0066] Synthesis Example 6: [Et₃Si]₂[B₁₀Br₁₀]

[0067] In an argon-filled glovebox, (H)₂[B₁₀Br₁₀]·6(H₂O) (330 mg, 0.32 mmol, 1.0 equiv ) was loaded into a 40 mL scintillation vial with no stir bar and no cap, followed by toluene (8.6 mL). Triethylsilane (1.12 g, 9.6 mmol, 30 equiv) was added, and the vial placed on a hot plate. No bubbling was observed. The temperature was slowly increased up to 100 °C while monitoring the mixture for gas generation. After 3 hours, the vial was removed from the heating block. The hot solution was added by pipette to another vial loaded with 60 °C heptane (8.7 g). Immediately the mixture turned cloudy white. It slowly became more translucent, and white crystals began to form. The mixture was left overnight to cool. The supernatant was decanted from the vial viapipette and the solid dried under vacuum. The target [Et₃Si]₂[B₁₀Br₁₀] was obtained as a white crystalline solid (282 mg, 77% yield).

[0068] Synthesis Example 7: [Et₃Si]₂[B₁₂F₁₂]

[0069] A solution of (H)₂[B₁₂F₁₂] (48-52% in water) (5 g) was concentrated under vacuum (15 mbar) at 60 °C to give a clear solution. Upon cooling, the clear solution became a white crystalline mass. The solid was heated under high vacuum first at 60 °C for 30 min, and then at 120 °C for 2 h to give (H)₂[B₁₂F₁₂]·6(H₂O). To 388 mg of the (H)₂[B₁₂F₁₂]·6(H₂O) (0.83 mmol, 1.0 equiv) was added at once Et3Si-H (1.9 g, 16.6 mmol, 20.0 equiv) along with 5 mL of benzene. Once the reagents are mixed, slow hydrogen evolution was immediately observed. The reaction mixture was warmed up to 60 °C, and left standing at that temperature for 1 h, after which time, rapid hydrogen evolution was observed. The reaction was left at that temperature for 5h, after which time hydrogen evolution has subsided and a colorless oil layer was formed at the bottom of the vial. Heptane (0.7 mL) was added at once to the mixture, and the mixture was left standing at room temperature for 5 days The product crystallizes as colorless needles. The supernatant was removed, the solids washed with heptane (2 x 2 mL), and the solids are dried in vacuo, yielding 430 mg of a white crystalline solid (88% yield).

[0070] Synthesis Example 8: [C₆H₇]₂[B₁₂Cl₁₂]

[0071] To a stirred suspension of [Et₃Si]₂[B₁₂Cl₁₂] (as prepared in Synthesis Example 1) (307.9 mg, 0.392 mmol) in benzene (3 mL) in a 20 mL glass vial was added trifluoromethanesulfonic acid (139 pL, 235 mg, 1.57 mmol, 4 equiv) and the mixture was stirred vigorously for 30 minutes to give a suspension. The suspension was a fine yellow solid in colorless supernatant which was concentrated under vacuum to ca. 1 mL to give a concentrate. To the concentrate was added pentane (5 mL) to give a mixture, and the mixture was briefly stirred, resulting in a supernatant. The supernatant was carefully decanted. This process was repeated with a further two portions of pentane (2 x 2.5 mL), resulting in a solid. The solid was dried under vacuum to give a white solid. NMR spectra were consistent with the formula [C6H7]2[B12CI12]-

[0072] Synthesis Example 9: (H)2[B12Cli2]-6(H2O)

[0073] In a well-ventilated fume hood, to a 500 mL round-bottom flask was added Cs₂[B₁₂H₁₂] (4 g, 9.8 mmol) and deionized (DI) water (200 mL). The flask was fitted with a water-cooled condenser. The top of the condenser was open to the atmosphere. The mixture was heated to 70 °C with stirring (magnetic stirrer). At this temperature, the solution was colorless and homogeneous. To the mixture was added trichloroisocyanuric acid (18.24 g, 78.5 mmol) in four portions over 48 h. During the reaction, a white crystalline solid precipitated. The progress of the reaction was monitored via NMR spectroscopy. When the reaction was complete, thesuspension was allowed to cool to ambient temperature and left to stand for 18 h. The suspension filtered through a disposable glass frit into a 250 mL round-bottom flask. To the stirring filtrate was added a solution of triethylamine hydrochloride (5.41 g, 39.3 mmol) in water (10 mL). This resulted in the immediate precipitation of a copious quantity of white solid. The suspension was filtered through a disposable glass frit and the filter cake was washed on the frit with DI water. The filtrant was dried under vacuum at 50 °C. ^H, ^C, and ^B NMR spectroscopy confirmed the identity of the isolated white solid as [Et₃NH]₂[B₁₂Cl₁₂] (6-85 g, 9.0 mmol, 92%).

[0074] The [Et₃NH]₂[B₁₂Cl₁₂] was suspended in DI water (10 mL) at ambient temperature in a 50 mL round-bottom flask. With stirring, a solution of NaOH (50% in water, 1.5 mL) was added dropwise, and the suspension became a hazy homogeneous solution. The solution was filtered, and the filtrate was concentrated using a rotary evaporator to a volume of ca. 5 mL. To the solution was added DI water (10 mL) and the solution was again concentrated using a rotary evaporator to a volume of ca. 5 mL. The concentration step was repeated one more time. To the solution was added a solution of cesium chloride (6.6 g, 39.2 mmol) resulting in the precipitation of a white crystalline solid. The suspension was heated until the solid dissolved. White crystals precipitated upon cooling to ambient temperature. The crystalline solid was isolated via filtration and dried under vacuum at 80 °C. 5.91 g. ^H, ^C, and ^B NMR spectroscopy confirmed the identity of the isolated white solid as Cs₂[B₁₂Cl₁₂] (73% yield).

[0075] A suspension of Cs₂[B₁₂Cl₁₂] (1 g) inD|water (10 mL) was stirred with prewashed (H+) ion exchange resin (10 g) for 10 minutes. The solution was decanted and the resin was rinsed with two portions of DI water (2 x 10 mL). The combined solution / washings were concentrated on a rotary evaporator at 50 °C and then under high vacuum at 50 °C to give a pale tan powder. The target compound was isolated in quantitative yield.

[0076] Synthesis Example 10: (H)2[B12Br12]-6(H2O)

[0077] In a 60 mL glass vial, (H+) ion exchange resin (10 g) was washed several times with 30 mL portions of DI water. To the washed resin, suspended in DI water (30 mL), was added Cs₂[B₁₂H₁₂] (1 g, 2.45 mmol) to give a mixture. The mixture was swirled periodically until all the Cs₂[B₁₂H₁₂] had dissolved (ca. 30 minutes). The mixture was filtered, and the resin was washed on the frit with a portion of DI water (30 mL). The filtrate was passed through a 0.45 pm PDVF syringe filter into a 250 mL round-bottom flask, and a further portion of DI water (40 mL) was added (total volume 100 mL). To the pale tan solution, with stirring, was added NaBr (7.56 g, 73.5 mmol, 30 equiv) followed by trichloroisocyanuric acid (3.42 g, 14.72 mmol, 6 equiv) and the flask was heated in an aluminum block (block temperature = 70 °C). The mixture, which became red-orange, was stirred for 42 h. An additional portion of trichloroisocyanuric acid (1.14 g, 4.91 mmol, 2 equiv) was added and the block temperature was raised to 100 °C. The mixturewas stirred for 96 h. NMR showed clean conversion to a single species. The solution was allowed to cool to ambient temperature. To the stirring solution was added solid sodium sulfite (3.7 g, 25.34 mmol), causing immediate decolorization. The mixture was filtered. To the filtrate was added a solution of [Et₃NH]Cl (1.34 g, 9.81 mmol, 4 equiv) in DI water (10 mL). A white solid precipitated. The suspension was stirred gently for 10 minutes, and then filtered. The retentate was washed with DI water, and dried under vacuum. The results of analyses by 1H, I^C, and 11 B NMR spectroscopy in acetone-dg, and by high-resolution mass spectrometry (HRMS), were consistent with [Et₃NH]₂[B₁₂Br₁₂]

[0078] To a suspension of [Et₃NH]₂[B₁₂Br₁₂] (1-0 g, 0.773 mmol) in DI water (10 mL) was added a 50 wt% solution of sodium hydroxide in water (1.0 mL, 1.515 g, [0.76 g NaOH], 19.0 mmol). To the suspension was added DI water (20 mL) and the mixture became a clear, homogeneous solution. The mixture was filtered through a 0.45 pm PVDF syringe filter. To the filtrate was added a solution of CsCI (521 mg, 3.10 mmol, 4 equiv) in DI water (5 mL). The clear, homogeneous solution was concentrated under reduced pressure at 50 °C to a volume of ca. 5 mL. At this point, white crystalline solid precipitated. To the suspension was added DI water (10 mL) and the suspension was concentrated under reduced pressure at 50 °C to a volume of ca. 5 mL. This dilution / concentration step was repeated a further two times. The suspension was filtered and the retentate was washed on the filter with cold water (5 mL) and dried under vacuum at 50 °C.

[0079] (H+) ion exchange resin (10 g) was suspended in 25 mL DI water overnight. The water was decanted, and the resin was washed with DI water (3 x 10 mL portions) and resuspended in DI water (10 mL). To the suspension was added Cs₂[B₁₂Br₁₂] and the mixture was swirled periodically over ca. 30 min. The mixture was decanted, and the resin was washed with DI water (10 mL). The decantate and washings were combined and passed through a 0.45 pm PVDF syringe filter to give a pale tan solution. The solution was concentrated under reduced pressure at 50 °C and then under high vacuum to give a pale tan powder in quantitative yield. 1 H and 11 B NMR were consistent with (H)2[B-|2Br-|21’6(H2O).

[0080] Synthesis Example 11: (H)2[B12li2]'6(H2O)

[0081] A microwave vial was charged with Cs₂[B₁₂H₁₂] (100mg, 0.26 mmol), acetic acid (10 mL), and iodine (2.11 g, 8.31 mmol) and the vial was heated to 230 °C for 2.5 h to form a solution. The solution was then quenched with a solution of Na2SO3 (1.8 g) in DI water (50 mL) to give a mixture. The mixture was filtered through Celite and to the filtrate was added solid [Et₃NH]Cl (79 mg, 0.572 mmol), resulting in the precipitation of solid. A small amount of thiscompound was taken up in acetonitrile / water and stirred vigorously with (H+) ion exchange resin for 2 h. 1H and 1 ^B NMR spectra were consistent with the formation of (H)2[B-|2H2]’6(H2O).

[0082] Synthesis Example 12: (H)2[B12CI11Br]-6(H2O)

[0083] A 250 mL flask was charged with DI water (150 mL) and Cs₂[B₁₂H₁₂] (6 g, 13.6 mmol). The mixture was heated until all the material dissolved. Then, [NBu₄]Br (9.25 g, 28.7 mmol) was added, resulting in a white precipitate. This was vigorously stirred for 3 h, after which the solid was washed extensively with water and dried under vacuum overnight, affording 8.35 g of (NBu₄)₂[B₁₂H₁₂]. Of this material, 4 g (6.38 mmol) was added to a 100 mL round-bottom flask charged with acetonitrile (20 mL) which was cooled to -15 °C (ethylene glycol / CO2). To the cooled solution was added a solution of A / -bromosuccinimide (1.14 g, 6.38 mmol) in acetonitrile (10 mL) dropwise over 10 minutes and the mixture was stirred for 1 h at -15 °C then overnight at room temperature. The mixture was then dried, extracted with CH2CI2, and the extracts were washed with three portions of water, dried over anhydrous Na2SO4 and filtered. The filtrate was dried to give 4.069 g of (NBu₄)₂[B₁₂H₁₁Br], with a minor impurity that could not be removed (88%). 2.77 g of this material (3.92 mmol) was dissolved in MeOH (20 mL) and to the solution was added Na[BPh₄] (2.69 g, 7.85 mmol), resulting in the precipitation of [NBu₄][BPh₄] as a white solid. The mixture was stirred for 1 h, then filtered and dried under vacuum. The filtrate was dried under vacuum and the resulting residue was suspended in H2O (25 mL). Concentrated HCI (25 mL) was then added. Then, a solution of NaOCI in water (~5%, 128 mL, 86.2 mmol) was added dropwise and the mixture was heated at the reflux temperature overnight. HRMS and 11 B NMR spectroscopy showed conversion to the desired product. The solution was cooled to room temperature and to the solution was added [Et₃NH]Cl (1.19 g, 8.64 mmol, 2.2 equiv), affording a white suspension. The suspension was stirred for 10 minutes then filtered and washed with water. The solid was washed into a separate flask with MeOH and to the solution was added (H+) ion exchange resin (3 g). The mixture was stirred slowly overnight. The solution gradually acquired a yellowish tint. The (H+) ion exchange resin was removed by filtration and the solution was concentrated to dryness under vacuum. 1.86 g of material was recovered. ”*H NMR analysis showed residual [Et3NH]. The material was redissolved in MeOH and to the solution was added (H+) ion exchange resin (6 g) and allowed to stand overnight. The mixture was again filtered and dried to give a tan solid that was free from residual [Et₃NH] as determined by NMR spectroscopy. (H)2[B12CI11Br]-6(H2O), 1.56 g, 62%).

[0084] Synthesis Example 13:(H)2[B10CI10]-6(H2O)

[0085] To a solution of Na₂[B₁₀H₁₀] (2 g> 12.2 mmol) in H2O (20 mL) was added concentrated HCI (10 mL). With stirring, a solution of NaOCI in water (6%, 302 mL, 243 mmol)was added to give a mixture. The mixture was heated at the reflux temperature overnight. and 11 B NMR spectra of the solution were consistent with the perchlorination of the boron cluster.

[0086] To the crude reaction solution was added [Et₃NH]Cl (3.69 g, 26.8 mmol, 2.2 equiv) with stirring. White precipitate was observed immediately and was isolated by filtration. The wet solid was dissolved in MeOH and washed into a round-bottom flask that contained (H+) ion exchange resin (30 g) that had been washed three times with water. The mixture was allowed to stand overnight. The mixture was filtered to remove the ion exchange resin, and to the filtrate was added a solution of CsOH in water (50 wt%, 14.6 g, 48.8 mmol, 4 equiv). White precipitate formed and the mixture was stirred overnight. The solid was isolated by filtration and the filtrate was retained. Analysis of the solid byNMR spectroscopy showed that residual [Et₃NH] was present and so the solid was taken up in 1:1 H2O / CH3CN and to the solution was added (H+) ion exchange resin. Analysis by 1H NMR spectroscopy showed no residual [Et₃NH] and so the solution was filtered and dried in vacuo affording 2.04 g of (H)₂[B₁₀Cl₁₀]·6(H₂O). The retained filtrate was free from [EtaNH] but was treated with (H+) ion exchange resin to ensure the complete removal of residual cesium cations. After standing overnight, the mixture was filtered and the water was removed under vacuum to give a further 2.74 g of (H)₂[B₁₀Cl₁₀]·6(H₂O) as a hygroscopic brownish solid. Total mass: 4.78 g (68%).

[0087] Synthesis Example 14: (H)2[B10Br10]-6(H2O)

[0088] To a solution of Na₂[B₁₀H₁₀](2 g, 12.2 mmol) in H2O (20 mL) was added concentrated HBr (48%, 10 mL) and NaBr (12.5 g, 121.5 mmol, 10 equiv). With stirring, a solution of NaOCI in water (6%, 180 mL, 145 mmol) was added to give a mixture. The mixture was heated at the reflux temperature for 3 h after which HRMS confirmed the completion of the reaction. The mixture was cooled and to the mixture was added [Et₃NH]Cl (3.69 g), resulting in the formation of a white solid. This was isolated by filtration and dissolved in methanol and transferred to a flask that contained 40 g of (H+) ion exchange resin that had been washed three times with water. The mixture was allowed to stand overnight. Analysis via NMR spectroscopy indicated that there was residual [Et₃NH], The solution was treated with a slight molar excess of CsOH, which produced a white solid. This was isolated by filtration. Both the solid and filtrate were separately treated with washed (H+) ion exchange resin in water and were allowed to stand overnight. The solutions, separately, were filtered and dried under vacuum to afford (H)2[B-|oBr-|o]’6(H20) as a light brown solid. (9.58 g total, 77%).

[0089] Synthesis Example 15: (H)2[B12Clg(OH)3]-6(H2O)

[0090] A 500 mL flask with a stir bar was charged with Cs₂[B₁₂H₁₂] (6 g, 15 mmol). The flask was cooled in an ice bath and aqueous H2SO4 (53% v / v, 120 mL) was added dropwise withvigorous stirring to give a white suspension. The flask was removed from the ice bath and a reflux condenser was affixed. The mixture was heated at 100 °C for 20 h. 11 B NMR showed conversion to the [B-|2(OH)3Hg] dianion. The solution was cooled to room temperature. A solution of NaOCI in water (10-15%, 60 mL) was added dropwise via an addition funnel over ca. 20 min. The reflux condenser was reattached and the solution was heated at 60 °C for 24 h. The reaction was monitored via 11 B NMR spectroscopy. A further volume of NaOCI solution (20 mL) was added and the mixture was heated at 85 °C for 24 h. To the cooled solution was added [NBu₄]Br (10.4 g) resulting in the precipitation of a white solid. The mixture was stirred for 1 h and then filtered. The isolated solid was recrystallized from boiling ethanol. A further crop of crystals was obtained by placing the mother liquor in the freezer overnight. NMR spectra were consistent with [NBu₄][B₁₂Cl₉(OH)₃]. Total mass 11.02 g, 75%.

[0091] To a solution of [NBu₄][B₁₂Cl₉(OH)₃] (1 g, 1.02 mmol) in acetonitrile (10 mL) in a 40 mL vial was added hexamethyldisilazane (745 pL, 3.55 mmol, 3.5 equiv). The mixture was stirred at 70 °C overnight. 11B NMR showed full conversion to the [B-|2Clg(OSiMe3)3] dianion.

[0092] [NBu₄]₂[B₁₂Cl₉(OSiMe₃)₃] (818 mg, 0.681 mmol) was dissolved in MeOH (10 mL). A solution of Na[BPh₄] (466 mg, 1.36 mmol, 2 equiv) was added, resulting in the precipitation of a white solid. After 1 h, the solution was filtered and the filtrate was concentrated to dryness. The residue was dissolved in MeOH / H2O, and to the solution was added (H+) ion exchange resin. The mixture was stirred overnight. 1H NMR spectroscopy showed the removal of the SiMe3 groups. The filtrate was dried in vacuo to give (H)₂[B₁₂Cl₉(OH)₃]·6(H₂O) as a tannish solid (357 mg).

[0093] Synthesis Example 16: (H)2[B12CII I(OH)] 6(H2O)

[0094] Cs₂[B₁₂H₁₂] (6.0 g, 15.0 mmol) and stir bar were added to a 500 mL roundbottom flask and the flask was placed into an ice bath. With vigorous stirring, dilute sulfuric acid was added dropwise using an addition funnel (120.0 mL, 38% v / v) to give a mixture. The mixture was heated at 90 °C for 5 h. Conversion to [B₁₂H₁₁(OH)]²⁻ was confirmed by ^B NMR spectroscopy. The reaction mixture was then allowed to cool to room temperature and a solution of NaOCI in water (120.0 mL, 6%) was slowly added to the flask via an addition funnel while the contents were stirred vigorously. The reaction mixture was then stirred at room temperature for 2 h. The addition funnel was then replaced by a reflux condenser and the reaction was heated at 60 °C for 24 h. An additional portion of NaOCI solution (40 mL) was added and the temperature was increased to 100 °C. The reaction was monitored via HRMS.

[0095] Upon the completion of the reaction, the mixture was allowed to cool and was quenched with sodium sulfite until all yellow color dissipated. The solution was then concentratedunder vacuum to give a white residue, which was recrystallized from hot water, giving 7.4 g of a white crystalline solid. The11B NMR spectra were consistent with the [B12Cl11(OH)]2−dianion with a low concentration of an impurity.

[0096] A portion of the solid (550 mg) was then suspended in a mixture of water and (H+) ion exchange resin (2 g) that had been washed with water. The mixture was allowed to stand overnight. The resin was removed by filtration, and the filtrate was concentrated under vacuum to afford the desired [H]2[B12Cl11(OH)]·6(H2O) product as a white solid (385 mg, 98%).

[0097] Synthesis Example 17: (H)2[B12H12]·6(H2O)

[0098] A 30 wt% solution of (H)2[B12H12] in water was concentrated under vacuum at 30 °C to give a deliquescent white solid (H)2[B-|2H-|2]‘6(H2O).Practical Examples:

[0099] General Procedure 1 for Examples 1-8 and Comparative Examples 1-12:

[0100] In a nitrogen filled glovebox, each species of Pre-Catalyst as prepared or obtained above and identified below (30-40 mg) was weighed in a glass vial and transferred to a stainless-steel reactor. The reactants (defined below) are weighed in a glass vial, and the catalyst containing vial was rinsed with the reactants and this mixture was also added to the stainless-steel reactor. The reactor was sealed and placed on an aluminum heating block. The reaction mixture was warmed up to 120 °C and left to react at that temperature for 2 hours after which time heat was turned off and the sample was cooled to room temperature naturally. An aliquot of this sample was dissolved in C6D6(0.5 g) and analyzed by multinuclear NMR spectroscopy (1H,29Si). The remainder of the reaction mixture was warmed up to 150 °C and left to react at that temperature for 2 hours after which time heat was turned off and the sample was cooled to room temperature naturally. An aliquot of this sample was dissolved in C6D6(0.5 g) and analyzed by multinuclear NMR spectroscopy (1H,29Si). The remainder of the reaction mixture was warmed up to 180 °C and left to react at that temperature for 2 hours after which time heat was turned off and the sample was cooled to room temperature naturally. An aliquot of this sample was dissolved in CgOg (0.5 g) and analyzed by multinuclear NMR spectroscopy (”*H, 29si). Table 2 below shows the amount of each Pre-Catalyst and reactant utilized in Examples 1-6 and Comparative Examples 1-11. C. E. indicates Comparative Example. For Comparative Example 12, no midpoint temperature of 150 °C was utilized, as shown in Table 3 below, but the procedure was otherwise identical to General Procedure 1.

[0101] General Procedure 2 for Comparative Example 13:

[0102] General Procedure 2 was the same as General Procedure 1, with the only difference being that the reaction mixture was first warmed to 180 °C and left to react at that temperature for 2 hours, and subsequently cooled to room temperature. An aliquot was sampled and analyzed after cooling, as in General Procedure 1.

[0103] General Procedure 3 for Comparative Example 14:

[0104] General Procedure 3 was the same as General Procedure 1, with the only difference being that 0.045 grams of hexamethyldisiloxane was added along with the reactants, after drying the hexamethyldisiloxane over 3A molecular sieves to ensure no residual moisture content.

[0105] Table 2: Examples 1-8 and Comparative Examples 1-14:

[0106] Table 3: Product distribution for each of Examples 1-8 and Comparative Examples 1-15 (yields in %)

[0107] The invention has been described in an illustrative manner, and it was to be understood that the terminology which has been used was intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. The invention may be practiced otherwise than as specifically described.

Claims

CLAIMSWhat is claimed is:

1. A method of preparing an organosilicon compound, said method comprising:combining (A) a hydridosilane, (B) an arene compound, and (C) a catalyst comprising a boron cluster and capable of coupling the arene compound (B) to a silicon atom of the hydridosilane (A), thereby preparing a reaction mixture comprising the organosilicon compound;wherein the hydridosilane (A) has the formula HSiQ3, where each Q is an individually selected halogen atom;wherein the organosilicon compound has the formula RSiQ3, where R is an aryl group, and each Q is independently selected and defined above.

2. The method of claim 1, wherein the catalyst (C) comprises a salt comprising one dianion having a charge of -2 and two cations, wherein the one dianion comprises the boron cluster.

3. The method of claim 2, wherein the one dianion has the formula (BaX^Y^-, where subscript a is 10 or 12, subscripts b and c are each independently selected integers greater than zero and b+c=a, wherein X and Y may be the same or different, and each X and each Y is independently selected from -SiR^ groups, where each R^ is independently an alkyl group or a halogen atom; halogen atoms, H, and hydrocarbyl groups, with the proviso that at least one X and / or at least one Y is a halogen atom.

4. The method of claim 2 or 3, wherein the two cations of the salt of the catalyst (C) are independently selected Brsnsted or Lewis acids.

5. The method of claim 4, wherein at least one cation comprises a Brgsnsted acid, and wherein the cation comprises a proton.

6. The method of claim 5, wherein the proton is associated with a molecule comprising a hydrocarbon.

7. The method of claim 4, wherein at least one cation comprises a Lewis acid.

8. The method of claim 7, wherein the Lewis acid comprises a silylium cation and / or a carbocation, wherein the silylium cation may optionally be associated with a molecule comprising a hydrocarbon, a substituted or unsubstituted arene, or a silane compound.

9. The method of claim 8, wherein the Lewis acid comprises the silylium cation, and wherein the silylium cation has the formula (R2)gSi+, where each R^ is independently selected from a substituted or unsubstituted hydrocarbyl group, H, and a halogen atom.

10. The method of claim 9, where each R^ is an independently selected alkyl group.

11. The method of any one preceding claim, wherein the method comprises combining the hydridosilane (A), the arene compound (B), and a pre-catalyst (C1) different from the catalyst (C), and wherein the catalyst (C) is formed in situ in the presence of the hydridosilane (A) and the arene compound (B).

12. The method of any one proceeding claim, carried out: (i) at an elevated temperature of from greater than room temperature to 250 °C; or (ii) at an elevated pressure greater than atmospheric pressure; or (iii) with a molar excess of the arene compound (B) relative to the hydridosilane (A), or (iv) any combination of (i)-(iii).

13. The method of any one preceding claim, wherein: (i): the hydridosilane (A) comprises HSiCIs; or (ii) the arene compound (B) comprises benzene; or (iii) the organosilicon compound comprises PhSiCl3, where Ph indicates phenyl; or (iv) the boron cluster comprises at least six halogen atoms; or (v) all of (i) to (iv).

14. The method of any one preceding claim, further comprising isolating the organosilicon compound from the reaction product.

15. The reaction product comprising the organosilicon compound prepared in accordance with the method of any one preceding claim.

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