Method of preparing a silylium / boron catalyst

Abstract

A method of producing a catalyst includes combining a boron cluster conforming to the formula H2BaXbYc·(ZOZ)x and an organosilicon compound conforming to the formula R3R4R5Si-Q to give a mixture, preparing a reaction mixture including catalyst, and isolating the catalyst. Subscript a is 10 or 12, each Z is independently H or an alkyl group, subscripts b and c are each independently selected integers greater than zero and b+c=a. Each X and each Y is independently selected from halogen atoms, H, alkyl groups, -SiR3 groups, where each R is independently an alkyl group or a halogen atom; and -OR1 groups. Each R1 is an independently selected alkyl group. At least one X and / or at least one Y is a halogen atom. Subscript x is >0. R3, R4, and R5 are each independently selected from hydrocarbyl groups and halogen atoms, and Q is selected from H and halogen atoms.

Description

METHOD OF PREPARING A SILYLIUM / BORON CATALYSTCROSS-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 / 784,583 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 producing a catalyst, and more specifically, a method of producing a catalyst by combining a boron cluster and an organosilicon compound, and an isolated catalyst formed in accordance with the same.DESCRIPTION OF THE RELATED ART

[0003] Catalysts are known in the art and are utilized in myriad industrial and commercial processes. Although most industrial and commercial catalysts have been identified and optimized over time, energy requirements and desire for efficiency remain significant.

[0004] For example, catalyst are utilized in making and ultimately using various silanes and organosilicon compounds. However, the creation of a silicon-carbon bond requires significant energy requirements. To form silicon-methyl bonds, SiO2 is first carbothermally reduced to Si, which is thermodynamic inefficient due to energy losses and incomplete conversion of materials. Si is then reacted with MeCI in the presence of a copper catalyst package in the Mueller-Rochow direct process.

[0005] Not only is the direct process energy intensive, but there’s little control of yield of byproducts. The main product of the direct process is dimethylchlorosilane (-85%), with the next highest components being MeSiCl3 and Me3SiCl Industry often desires more Me3SiCI as an end-blocker for organopolysiloxane polymerization. MeSiCl3 is typically produced in excess. Increasing production of Me3SiCl via the direct process also results in greater production of MeSiCI3.BRIEF SUMMARY

[0006] The present disclosure provides a method of producing a catalyst. The method comprises the step of combining a boron cluster and an organosilicon compound to give a mixture. The method further comprises preparing a reaction mixture comprising the catalyst and isolating the catalyst. The boron cluster is of the general formula H2BaXbYc·(ZOZ)x. Subscript a is 10 or 12, each Z is independently H or an alkyl group, subscripts b and c are each independently selected integers greater than zero and b+c=a. X and Y may be the same or different, and each X and each Y is independently selected from halogen atoms, H, alkyl groups, -SiR3 groups, where each R is independently an alkyl group or a halogen atom, and -OR^ groups. Each R1 is an independently selected alkyl group. At least one X and / or at least one Y is ahalogen atom, and subscript x is >0. The organosilicon compound has the general formula R3R4R5Si-Q. R3, R4, and R5are each independently selected from hydrocarbyl groups and halogen atoms, and Q is selected from H and halogen atoms.

[0007] The present disclosure further provides an isolated catalyst formed in accordance with the method.DETAILED DESCRIPTION

[0008] A method of producing a catalyst is disclosed. The catalyst prepared via the method has excellent catalytic properties and can be utilized in myriad reactions involving organosilicon compounds, as well as other end uses.

[0009] The method comprises combining a boron cluster and an organosilicon compound to give a mixture. The boron cluster is of the general formula H2BaXbYc·(ZOZ)x, where subscript x is > 0, subscript a is 10 or 12, each Z is independently H or an alkyl group, 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 halogen atoms, H, alkyl groups, -SiR3 groups, where each R is independently an alkyl group or a halogen atom, and -OR”* groups, where each R^ is an independently selected alkyl group, with the proviso that at least one X and / or at least one Y is a halogen atom.

[0010] The halogen atoms represented by X and Y (or R) 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 halogen atom is Cl or F. In specific embodiments, when X and / or Y is a halogen atom, the halogen atom is Cl.

[0011] In one embodiment, at least one X and / or Y is an -SiR3 groups, where each R is independently an alkyl group or a halogen atom. When each R is methyl, the -SiR3 group is a trimethylsilyl group. When two of R are methyl and the other is chlorine, the -SiR3 group is a dimethylchlorosilyl group. When all of R are chlorine, the -SiR3 group is a trichlorosilyl group.

[0012] In one embodiment, at least one X and / or Y is an -OR^ group, where R^ is H, i.e., at least one X and / or Y is an OH group. In other embodiments when at least one X and / or Y is an -OR”* group, each R^ is an independently selected alkyl group. In such embodiments, each R1 may be linear, branched, cyclic (e.g., cycloalkyl), or combinations thereof. In certain embodiments, each R^ is linear or branched. In specific embodiments, each R^ is linear.

[0013] 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 ornon-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, 2,2-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.

[0014] 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 groups and aromatic hydrocarbyl groups. In more specific embodiments, the hydrocarbyl group is selected from alkyl groups and aryl groups. Examples of suitable alkyl groups for X, Y, R, and R^ include methyl, ethyl, propyl (e.g., isopropyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tertbutyl, 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.

[0015] In certain embodiments, each R^ independently has from 1 to 8, alternatively from 1 to 7, alternatively from 1 to 6, alternatively from 1 to 5, alternatively from 1 to 4, alternatively from 1 to 3, alternatively from 1 to 2, alternatively 1, carbon atoms.

[0016] 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.

[0017] In moiety (ZOZ)X, each Z is independently H or an alkyl group. In one embodiment, each Z is H such that the moiety is HOH, or water. In another embodiment, one Z is an alkyl group and one Z is H such that moiety (ZOZ)Xis an alcohol whose species is a function of the alkyl group. In certain embodiments, when Z is an alkyl group, the alkyl group has from 1 to 10, alternatively from 1 to 8, alternatively from 1 to 7, alternatively from 1 to 6, alternatively from 1 to 5, alternatively from 1 to 4, alternatively from 1 to 3, alternatively from 1 to 2, alternatively 1, carbon atoms. In another embodiment, each Z is an alkyl group such that moiety (ZOZ)Xis an ether moiety. When each Z is an alkyl group, the alkyl groups may be linked together such that moiety (ZOZ)Xis cyclic or has a ring structure. As but one example, moiety (ZOZ)Xcan be tetra hydrofuran (THF). In such embodiments, each Z can be considered a C2 hydrocarbon moiety linked together (or one Z can be a C1 hydrocarbon moiety and the other Z can be a C3 hydrocarbon moiety linked together, as the total number of carbon atoms linked together in such an embodiment would be four). As described below, the number of moieties (ZOZ)Xis representative and may vary, and different species of moiety (ZOZ)Xmay be presented together in the same boron cluster.

[0018] Exemplary examples of the boron cluster include (H)2[B12Cl12]·6(H2O), (H)2[B12Br12]·6(H2O), (H)2[B12I12]·6(H2O), (H)2[B12Cl11Br]·6(H2O), (H)2[B10Cl10]·6(H2O), (H)2[B10Br10]·6(H2O), (H)2[B12Cl11(OH)]·6(H2O), (H)2[B12F12]·6(H2O), (H)2[B12Cl9(OH)3]·6(H2O), (H)2[B12Cl12]·4(MeOH), (H)2[B12Cl12]·4(EtOH)·2(H2O), (H)2[B12Cl12]·4(C4H8O)·2(H2O) (where C4H8O is tetrahydrofuran) and combinations thereof. One of skill in the art readily appreciates how, in any of the exemplary 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.

[0019] In specific embodiments, boron cluster comprises the hydronium salt of a boron cluster (a dianionic boron cluster). As described above, 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 non-coordinating, the associated proton or counterion is strongly acidic. Because the proton or counterion is strongly acidic, the proton will interact very strongly with water or alcohol molecules. Typically, the boron cluster cannot be completely dried to become free of ZOZ moieties (e.g. water or alcohol) by traditional means (e.g. heating under vacuum). Generally, even after drying off excess ZOZ moieties under vacuum, from two to six or more ZOZ molecules or more 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.Representation Representation"Detailed"Representation

[0020] The organosilicon compound has the general formula R3R4R5si-Q; where R3, R4, and R^are each independently selected from hydrocarbyl groups and halogen atoms, and Q is selected from H and halogen atoms.

[0021] Specific examples of hydrocarbyl groups and halogen atoms are described above.

[0022] In one embodiment, Q is H such that the organosilicon compound is a hydridosilane. Specific examples of suitable hydridosilanes include methyldichlorosilane, dimethylchlorosilane, triethylsilane, and tri-n-butylsilane. One of skill in the art understands other species within the general formula of the organosilicon compound, and that methyl and chloro may be replaced with other hydrocarbyl groups and halogen atoms in these specific examples.

[0023] In other embodiments, Q is a halogen atom such that the organosilicon compound is free from silicon-bonded hydrogen atoms. Specific examples of such organosilicon compounds include trimethylchlorosilane, dimethyldichlorosilane, and triethylchlorosilane. One of skill in the art understands other species within the general formula of the organosilicon compound, and that methyl and chloro may be replaced with other hydrocarbyl groups and halogen atoms in these specific examples.

[0024] The organosilicon compound and / or the boron cluster 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 organosilicon compound and the boron cluster may be combined neat. Further still, the organosilicon compound and / or the boron cluster may also be utilized neat but then may be combined with other components, e.g. a vehicle or solvent.

[0025] Alternatively, the vehicle may comprise an organic solvent. Examples of organic solvents include: aromatic hydrocarbons, such as benzene, toluene, xylene, mesitylene, etc.; 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,; and the like, as well as derivatives, modifications, and combinations thereof.

[0026] The vehicle, if utilized, is different from the organosilicon compound and the boron cluster.

[0027] A reaction mixture comprising the catalyst is formed upon combining the boron cluster and the organosilicon compound.

[0028] 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 found in a hydridosilane. The boron cluster will “dry” in-situ through reaction of the Si-H containing material with the acidic water, forming a by-product disiloxane. More specifically, the proton may react with a hydridic Si-H bond when present in the organosilicon compound to make silylium cation and H2. Two silylium cations can then react with water or alcohol 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 the main counterion to the boron cluster (di)anion. 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.

[0029] 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.

[0030] The catalyst may comprise a halosilylium ion, typically a chlorosilylium ion. The halosilylium is cationic and associated with the boron cluster, which is anionic and is the counterion.

[0031] In certain embodiments, the catalyst comprises a salt comprising one dianion having a charge of -2 and two cations, wherein the one dianion comprises the boron cluster.

[0032] In specific embodiments, the one dianion has the formula (BaXbYc)2-, where X, Y, and subscripts a-c are defined above for the boron cluster.

[0033] Typically, the two cations of the salt of the catalyst are independently selected Brønsted or Lewis acids. In one embodiment, each of the two cations of the catalyst are independently selected Brønsted acids. In another embodiment, each of the two cations of the catalyst are independently selected Lewis acids. In yet another embodiment, one cation is a Brønsted acid, and the other is a Lewis acid.

[0034] In one embodiment, at least one cation comprises, alternatively both cations comprise, an independently selected Brsnsted 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. The molecule may be, for example, a hydrocarbon or a substituted or unsubstituted arene compound. The molecule may alternatively be a silane compound. Typically, the molecule, if present in association with the cation, is free of oxygen atoms.

[0035] 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 R2 is 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 R is an independently selected alkyl group. In other embodiments, at least one R^ is a halogen atom, and the remaining of R^ are alkyl groups.

[0036] The silylium cation may optionally be associated with a substituted or unsubstituted arene, a hydrocarbon and / or a silane compound. Arenes may be optionally be substituted with one or more alkyl groups. Specific examples of suitable hydrocarbons include those described above for X or 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.

[0037]

[0038] 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 silane compound, or an unsaturated hydrocarbon

[0039] Specific examples of suitable carbocations include silyl-benzenium and other silyl-arenium cations, One specific example of a suitable arenium cation is silyl-benzenium. One ofskill in the art readily understands other suitable carbocations based on aromatic and unsaturated aliphatic hydrocarbons.

[0040] In certain embodiments, the catalyst has the general formula [BaXbYc][SiR3R4R5]2where X, Y, R3, R4, R^ and subscripts a, b, and c are defined above. Depending on a selection of X, Y, R3, R4, R^ and subscripts a, b, and c, the catalyst may be, for example, [Et3Si]2[B12Cl12], [Et3Si]2[B12Br12], [Et3Si]2[B12Cl12], [Et3Si]2[B12I12], [Et3Si]2[B12Cl11Br], [Et3Si]2[B10Cl10], [Et3Si]2[B10Br10], [Et3Si]2[B12F12], [i-Bu3Si]2[B12Cl12], [n-Bu3Si]2[B12Cl12], [R3R4R5]2[B12Cl12], and combinations thereof.

[0041] The catalyst may form at ambient conditions in the mixture upon combining the organosilicon compound and the boron cluster. Alternatively, any ambient condition (temperature, pressure, etc.) can be selectively modified to prepare the reaction mixture and the catalyst. For example, in certain embodiments, preparing the reaction mixture comprises heating the mixture at an elevated temperature of from greater than room temperature to 200 °C, alternatively from 30 to 180, alternatively from 40 to 160, alternatively from 40 to 150, alternatively from 40 to 140, °C.

[0042] In these or other embodiments, the reaction mixture is prepared in an open system, and gas generated upon preparing the reaction mixture is removed while heating the mixture. In certain embodiments, the method further comprises isolating the catalyst from the reaction mixture. The method of isolating the catalyst is not limited and can be any suitable method known to one of skill in the art. In certain embodiments, isolating the catalyst comprises: (i) precipitating the catalyst in the reaction mixture; or (ii) drying the reaction mixture to give the catalyst (for example, at ambient conditions); or (iii) volatilizing the reaction mixture to give the catalyst (for example, at elevated temperatures to accelerate volatilization).

[0043] In specific embodiments, isolating the catalyst comprises precipitating the catalyst in the reaction mixture. The catalyst can be precipitated in the reaction mixture via numerous techniques. For example, in one embodiment, precipitating the catalyst in the reaction mixture comprises maintaining a temperature of the reaction mixture of from -70 to 100, alternatively from -70 to 50 °C. In these or other embodiments, precipitating the catalyst in the reaction mixture comprises reducing the temperature of the reaction mixture after the step of heating. Alternatively still, the method of isolating the catalyst can comprise the step of disposing a vehicle in the reaction mixture to give a diluted reaction mixture, where the catalyst is precipitated from the diluted reaction mixture. Suitable examples of vehicles are described above. In certain embodiments, the vehicle comprises a hydrocarbon vehicle. Upon isolating the catalyst, the catalyst may be washed and dried to give an isolated catalyst. The isolated catalyst can be utilized end use applications, including as a pre-catalyst, in the applications referenced below.

[0044] The method of preparing the catalyst can be carried out in situ during a reaction involving at least one halosilane. For example, the catalyst can be prepared during a reaction as described in U. S. Provisional Patent Application No. 63 / 784,573 filed on 07 April 2025, U. S. Provisional Patent Application No. 63 / 784,593 filed on 07 April 2025, and U. S. Provisional Patent Application No. 63 / 784,600 filed on 07 April 2025, which are each incorporated by reference herein.

[0045] 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, Acros Organics, Sigma-Aldrich, etc.) and utilized as received.

[0046] 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 their sources.

[0047] Table 1: Materials Utilized and SourcesSynthesis Examples

[0048] Synthesis Example 1: (H)2[B12CI12]-6(H2O)

[0049] 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) to give a mixture. 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 ^B NMR spectroscopy. When the reaction was complete, the suspension was allowed to cool to ambient temperature and left to stand for 18 h. The suspension was 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 retentate was dried under vacuum at 50 °C. 1H, 13C, and ^B NMR spectroscopy confirmed the identity of the isolated white solid as [Et3NH]2[B12Cl12] (6.85 g, 9.0 mmol, 92%).

[0050] The [Et3NH]2[B12Cl12]wassuspended 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 ofca. 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. 1H, 13C, andNMR spectroscopy confirmed the identity of the isolated white solid as Cs2[B12Cl12] 73% yield.

[0051] A suspension of Cs2[B12Cl12] (1 g) in DI 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 ((H)2[B12CI12] 6(H2O)) was isolated in quantitative yield.

[0052] Synthesis Example 2: (H)2[B12Br12]-6(H2O)

[0053] 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 µm PVDF 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 mixture was stirred for 96 h. 11 B 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 of the red-orange solution. 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 1 H, 13C and 11B NMR spectroscopy in acetone-dg, and by high-resolution mass spectrometry (HRMS), were consistent with [Et3NH]2[B12Br12].

[0054] 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 µm 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.

[0055] (H+) ion exchange resin (10 g) was suspended in 25 mL DI water over night. 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 µm 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.1H and 11B NMR were consistent with (H)2[B12Br12]·6(H2O).

[0056] Synthesis Example 3: (H)2[B12li2]-6(H2O)

[0057] A microwave vial was charged with Cs2[B12H12] (100 mg, 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). 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 this compound was taken up in aceton itrile / water and stirred vigorously with (H+) ion exchange resin for 2 h.and NMR spectra were consistent with the formation of (H)2[B12I12]·6(H2O).

[0058] Synthesis Example 4: (H)2[B12CI11 Br] 6(H2O)

[0059] A 250 mL flask was charged with DI water (150 mL) and Cs2[B12H12] (6 g, 13.6 mmol) to give a mixture. 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 N-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 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 [B12Cl11Br] dianion). 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. NMR analysis showed residual [HNEt3]. 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[B12Cl11Br]·6(H2O), 1.56 g, 62%).

[0060] Synthesis Example 5: (H)2[B10CIIO]-6(H20)

[0061] 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. ^H and 11 B NMR spectra of the solution were consistent with the perchlorination of the cage.

[0062] 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 by ^H NMR spectroscopy showed that residual [Et3NH] waspresent and so the solid was taken up in 1:1 H2O / CH3CN and to the solution was added (H+) ion exchange resin. Analysis byNMR 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 [Et3NH] 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 of product was 4.78 g (68%).

[0063] Synthesis Example 6: (H)2[B-|oBr-|o]’6(H20)

[0064] 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] cation. 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-|ol‘6(H20) as a light brown solid (9.58 g total, 77%).Practical Examples:

[0065] Example 1: [Et3Si]2[B12CI12]

[0066] 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 of triethylsilane (1.45 g, 12.45 mmol, 50.0 equiv) along with toluene (1.0 mL) to give a reaction mixture. 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%). 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[B12Cl12].

[0067] Example 2: [Et3Si]2[B12Br-|2]

[0068] In an argon-filled glovebox, to (H)2[B-|2Br-|21‘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) to give a reaction mixture. 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-d6 and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et3Si·C6D6]2[B12Br12].

[0069] Example 3: [Et3Si]2[B12H2]

[0070] In an argon-filled glovebox, to (H)2[B-|2ll2]’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) to give a reaction mixture. 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.

[0071] Example 4: [Et3Si]2[B12CI-| -| Br]

[0072] 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) to give a reaction mixture. 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-d6 and the solution was analyzed by NMR spectroscopy, revealingthe 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.

[0073] Example 5: [Et3Si]2[B1oCI1o]

[0074] 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 to form a mixture, 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-d6 and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et3Si·C6D6]2[B10Cl10].

[0075] Example 6: [Et3Si]2[B10Br10]

[0076] 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 was 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 via pipette and the solid was dried under vacuum. The target [Et3Si]2[B10Br10] was obtained as a white crystalline solid (282 mg, 77% yield).

[0077] Example 7: [Et3Si]2[B12Fi2]

[0078] A solution of (H)2[B12F12] (48-52 wt% 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). In an argon filled glovebox, to 388 mg of (H)2[B-|2F-|21‘6(H2O) (0.83 mmol, 1.0 equiv) in a 40 mL scintillation vial with no stir bar and no cap was added in a single portion triethylsilane (1.9 g, 16.6 mmol, 20.0 equiv) and benzene (5 mL). The evolution of gas was immediately observed. The reaction mixture was heated to 60 °Cand allowed to stand at that temperature for 1 h. During this time, rapid evolution of gas was observed. The reaction was allowed to stand at 60 °C for 5 h, after which time the evolution of gas had stopped and a colorless oily layer had formed at the bottom of the vial. Heptane (0.7 mL) was added in a single portion to the mixture, and the mixture was allowed to stand at room temperature for 5 days. The product crystallized as colorless needles. The supernatant was removed, the solids were washed with heptane (2 x 2 mL) and then dried under vacuum, yielding 430 mg of a white crystalline solid (88% yield). A small amount of the solid (20 mg) was heated at 70 °C in benzene-dg and the solution was analyzed by NMR.

[0079] Example 8: [i-Bu3Si]2[B12Cl12]

[0080] To 312.7 mg of (H)2[B12Cl12]·6(H2O) (0.46 mmol, 1.0 equiv) was added all at once i-Bu3Si-H (2.7 g, 13.8 mmol, 30.0 equiv) along with 10 mL of toluene. The reaction mixture was slowly warmed up to 60 °C and consistent hydrogen evolution was observed. The reaction mixture was left at that temperature for 3 hours, after which time the solid had mostly turned to an orange oil. The reaction mixture was further heated to 100 °C for 30 minutes to ensure reaction completion, and the solution was left standing at room temperature overnight. A white solid crystallized. The supernatant was removed, and the solids were rinsed with toluene (3 x 2mL). The solids were dried in vacuo, yielding 408 mg of a white powder (0.43 mmol, 93% yield).

[0081] Example 9: [n-Bu3Si]2[B-|2CI-|2]

[0082] To 397 mg of (H)2[B12Cl12]·6(H2O) (0.59 mmol, 1.0 equiv) was added all at once n-Bu3Si-H (1.36 g, 9.36 mmol, 16.0 equiv) along with 3 mL of toluene to give a reaction mixture. The reaction mixture was slowly warmed up to 60 °C and consistent hydrogen evolution was observed. The reaction mixture was left at that temperature for 3 hours, after which time the solid had mostly turned to an orange oil. The reaction mixture was further heated to 100 °C for 30 minutes to ensure reaction completion. Heptane (10 mL) was added at once, and the reaction mixture was stirred vigorously and the solution was left standing at room temperature overnight. A white solid crystallized. The supernatant was removed, and the solids were rinsed with heptane (3 x 2mL). The solids were dried in vacuo, yielding 356 mg of a white powder (0.37 mmol, 63% yield).

[0083] Example 10: [R3Si]2[B12Cl12], where R is independently Me or Cl

[0084] In a nitrogen filled glovebox, to 0.144 mg of (H)2[B12Cl12]·6(H2O) (0.21 mmol, 1.0 equiv) was added all at once Me3SiCl (2.17 g, 20.0 mmol, 95.1 equiv) to give a mixture. The mixture was transferred to a stainlesssteel vessel and heated to 180 °C for 200 minutes, then left to cool down naturally. The liquids were removed, and heptane (4 mL) was added to the resulting solids. The mixture was heated at 80 °C for 1 h, then the liquids were removed. Heptane (4 mL) was added to the solids, and the mixture was heated at 80 °C for 1 h, then the liquids wereremoved and the solids were dried in vacuo. The solids were taken and placed in a clean stainless-steel vial, then an additional charge of Me3SiCl was introduced (2.17 g, 20.0 mmol, 95.1 equiv) to give a reaction mixture. The reaction mixture was heated to 180 °C for 154 minutes, then left to cool down naturally. The liquids were removed, and heptane (4 mL) was added to the solids to give another mixture. The mixture was heated at 80 °C for 1 h, then the liquids were removed. Heptane (4 mL) was added to the solids to give yet another mixture, and the mixture was heated at 80 °C for 1 h, then the liquids were removed in vacuo yielding the title compound.

[0085] Example 11: [R3Si]2[B12Cl12], where R is independently Me or Cl

[0086] In a nitrogen filled glovebox, to 141 mg of (H)2[B12Cl12]·6(H2O) (0.21 mmol, 1.0 equiv) was added at once Me2SiCl2 (2.14 g, 16.6 mmol, 79.0 equiv) to give a mixture. The mixture was transferred to a stainless-steel vessel and heated to 180 °C for 200 minutes, then left to cool down naturally. The liquids were removed, and heptane (4 mL) was added to the solids to give another mixture. The mixture was heated at 80 °C for 1 h, then the liquids were removed. Heptane (4 mL) was added to the solids to give another mixture, and the mixture was heated at 80 °C for 1 h, then the liquids were removed and the solids were dried in vacuo. The solids were taken and placed in a clean stainless-steel vial, then an additional charge of Me2SiCl2 was introduced (2.16 g, 16. mmol, 79.0 equiv) to give a reaction mixture. The reaction mixture was heated to 180 °C for 154 minutes, then left to cool down naturally. The liquids were removed, and heptane (4 mL) was added to the solids to give another mixture. The mixture was heated at 80 °C for 1 h, then the liquids were removed. Heptane (4 mL) was added to the solids, and the mixture was heated at 80 °C for 1 h, then the liquids were removed in vacuo yielding the title compound.

[0087] Example 12: [Et3Si]2[B12Cl12] - Alternative Synthesis from Et3SiCl

[0088] In a nitrogen filled glovebox, to 40 mg of (H)2[B12Cl12]·6(H2O) (0.059 mmol, 1.0 equiv) was added all at once Et3SiCl (0.2 g, 1.71 mmol, 29.0 equiv) along with benzene (1.0 mL). The reaction mixture was heated to 80 °C for 72 hours, then the reaction mixture was left to cool down to room temperature naturally. Heptane was layered, and the solution was left standing at room temperature for 1 week. Colorless crystals formed, and X-ray crystallography confirmed the formation of [Et3Si]2[B12Cl12].

[0089] 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 producing a catalyst, said method comprising:combining a boron cluster and an organosilicon compound to give a mixture; preparing a reaction mixture comprising the catalyst from the mixture; andisolating the catalyst;wherein the boron cluster is of the general formula H2BaXbYc·(ZOZ)x, where subscript a is 10 or 12, each Z is independently H or an alkyl group, 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 halogen atoms, H, hydrocarbyl groups, -SiR3 groups, where each R is independently an alkyl group or a halogen atom; and -OR”* groups, where each R^ is an independently selected alkyl group, with the proviso that at least one X and / or at least one Y is a halogen atom, and where subscript x is >0;wherein the organosilicon compound has the general formula R3R4R5si-Q; where R3, R4, and R^are each independently selected from hydrocarbyl groups and halogen atoms, and Q is selected from H and halogen atoms.

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

3. The method of claim 2, wherein at least one cation comprises a Lewis acid.

4. The method of claim 3, wherein the Lewis acid comprises a silylium cation.

5. The method of claim 4, wherein the silylium cation has the formula (R2)3Si+, where each R^ is independently selected from H, a substituted or unsubstituted hydrocarbyl group and a halogen atom.

6. The method of claim 5, where each R^ is an independently selected alkyl group.

7. The method of any one preceding claim, wherein the catalyst has the general formula [BaXbYc][SiR3R4R5]2, where X, Y, R^, R4, R5 and subscripts a, b, and c are defined above.

8. The method of any one preceding claim, wherein: (i) preparing the reaction mixturecomprising heating the mixture at an elevated temperature of from greater than room temperature to 200 °C; or (ii) preparing the reaction mixture is carried out in an open system; or (iii) preparing the reaction mixture is carried out at room temperature; or (iv) gas generated by preparing the reaction mixture is removed while heating the mixture; or (v) any combination of (i) to (iv).

9. The method of any one preceding claim, wherein isolating the catalyst comprises: (i) precipitating the catalyst in the reaction mixture; or (ii) drying the reaction mixture at room temperature to give the catalyst; or (iii) volatilizing the reaction mixture at an elevated temperature to give the catalyst.

10. The method of claim 9, wherein isolating the catalyst comprises precipitating the catalyst in the reaction mixture, and wherein: (i) precipitating the catalyst in the reaction mixture comprises maintaining a temperature of the reaction mixture of from -70 to 100 °C; or (ii) precipitating the catalyst in the reaction mixture comprises reducing the temperature of the reaction mixture after the step of heating; or (iii) both (i) and (ii).

11. The method of claim 10, further comprising the step of disposing a vehicle in the reaction mixture to give a diluted reaction mixture, and wherein the catalyst is precipitated from the diluted reaction mixture.

12. The method of claim 11, wherein the vehicle comprises a hydrocarbon vehicle.

13. The method of any one preceding claim carried out in situ during a reaction involving at least one halosilane.

14. The method of any one preceding claim, further comprising washing and drying the catalyst to give an isolated catalyst.

15. The isolated catalyst formed in accordance with the method of claim 14.

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