Catalytically active salt

Abstract

A catalytically active salt including at least one boron cluster dianion and at least one cation. The cation includes a silylium cation having at least one silicon-bonded halogen atom. A composition including the catalytically active salt and at least one halosilane compound is also disclosed. A use of the catalytically active salt to couple an arene compound to a silicon atom of a hydridosilane compound is further disclosed. A use of the catalytically active salt to facilitate the exchange of one silicon-bonded alkyl group of a first silane molecule with a silicon-bonded halogen atom of a second silane molecule is also disclosed.

Description

CATALYTICALLY ACTIVE SALTCROSS REFRENCE 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 / 784,608 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 catalytically active salts and, more specifically, to a silylium boron cluster salt, a composition comprising the same, and uses of the silylium boron cluster salt.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, catalysts 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, SiO2is first carbothermally reduced to Si, which is thermodynamically inefficient due to loss issues. 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 production of byproducts also reduces efficiency. The main product of the direct process is dimethyldichlorosilane (-85%), with the next highest components being MeSiCl3 and MesSiCL Industry often desires more MesSiCI as an end-blocker for organopolysiloxane polymerization. MeSiCl3 is typically produced in excess. Increasing production of MesSiCI via the direct process also results in greater production of additional MeSiCIs production.BRIEF SUMMARY

[0006] The present disclosure provides a catalytically active salt. The catalytically active salt comprises at least one boron cluster dianion and at least one cation. The cation comprises a silylium cation having at least one silicon-bonded halogen atom.

[0007] The present disclosure further provides a composition comprising a catalytically active salt and at least one halosilane compound.

[0008] The present disclosure also provides a use of the catalytically active salt to couple an arene compound to a silicon atom of a hydridosilane compound.

[0009] The present disclosure further provides a use of the catalytically active salt to facilitate the exchange of one silicon-bonded alkyl group of a first silane molecule with a silicon-bonded halogen atom of a second silane molecule.DETAILED DESCRIPTION

[0010] The present disclosure provides a catalytically active salt. The catalytically active salt can be utilized in myriad reactions involving organosilicon compounds, as well as other end uses, as described below.

[0011] The catalytically active salt comprises at least one boron cluster dianion. The boron cluster dianion generally comprises a plurality of boron atoms clustered together. Boron clusters are extremely stable and generally do not decompose under reaction conditions. In addition, boron clusters are substantially non-coordinating, thus they do not significantly quench the Lewis acidity of silylium cations, as described below. Without being limited by theory, it’s believed that the combination of a highly Lewis acidic “free” silylium cation and a highly stable anionic boron cluster is what makes catalytic activity of the catalytically active salt possible. In one embodiment, the atoms of the boron cluster dianion are arranged in a closo-cage structural arrangement.

[0012] For purposes of clarity, the boron cluster dianion is referred to herein as “the dianion,” which applies to at least one dianion, alternatively all dianions, in the catalytically active salt. When the catalytically active salt comprises more than one boron cluster dianion, each dianion may be independently selected. The catalytically active salt may comprise two or more dianions that are different from one another by structure, e.g., the number of boron atoms or other substituents. In one embodiment, the catalytically active salt comprises one dianion.

[0013] In specific embodiments, the one dianion has the formula (BgXb)^, where subscript a is 10 or 12, subscript b=a, and each X is independently selected from -SiR^ groups, where each R^ is independently a hydrocarbyl group, a halogen atom, or H; halogen atoms; H; hydrocarbyl groups; and -OR^ groups, where each R^ is independently H, an alkyl group, or a silyl group; methanesulfonyloxy (mesyloxy) groups, tosyloxy groups, triflyloxy groups, nitrophenylsulfonyloxy (nosyloxy) groups, bromo-phenylsulfonyloxy (brosyloxy) groups, and OC(O)R3 group, where R^ is an alkyl group.

[0014] The halogen atoms represented by X (or R^) can be fluorine (F), chlorine (Cl), bromine (Br), iodine (I). In certain embodiments, when X is a halogen atom, the halogen atom is Br, Cl, or F. In yet other embodiments, when X is a halogen atom, the halogen atom is Cl or Br. In specific embodiments, when X is a halogen atom, the halogen atom is CL

[0015] In one embodiment, at least one X 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.

[0016] In one embodiment, at least one X is an -OR^ group, where R^ is H, i.e., at least one X is an OH group. In other embodiments when at least one X is an -OR^ group, each R^ is an independently selected alkyl group. In such embodiments, each R 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. 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.

[0017] In one embodiment, at least one X is an -OR^ group, where R^ is a silyl group. The silyl group is typically an -SiR^ group, where each R^ is independently selected and defined above, such that X is of formula -OSiR3- In another embodiment, the silyl group represented by R2 includes a siloxane bond such that X is a siloxy moiety. Typically, even when R^ includes a siloxane bond, R^ is linear and free from T or Q siloxy units.

[0018] In one embodiment, at least one X is a hydrocarbyl group, which are independently selected when more than one X 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., iso-propyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g., isopentyl, neopentyl, and / or tertpentyl), hexyl, as well as branched saturated hydrocarbon groups of 6 carbon atoms. Suitable aryl groups are exemplified by, but not limited to, phenyl, tolyl, xylyl, naphthyl, benzyl, and dimethyl phenyl. Suitable alkenyl groups include vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, pentenyl, heptenyl, hexenyl, and cyclohexenyl groups. Suitable monovalent halogenated hydrocarbon groups include, but are not limited to, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms. Suitable halogenated alkyl groups are exemplified by, but not limited to, the alkyl groups described above where one or more hydrogen atoms is replaced with a halogen atom, such as F or Cl. For example, fluoromethyl, 2-fluoropropyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 4,4,4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, and 8, 8, 8,7,7-pentafluorooctyl, 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4-difluoro-5-methylcycloheptyl, chloromethyl, chloropropyl, 2-dichlorocyclopropyl, and 2,3-dichlorocyclopentyl are examples of suitable halogenated alkyl groups. Suitable halogenated aryl groups are exemplified by, but not limited to, the aryl groups described above where one or more hydrogen atoms is replaced with a halogen atom, such as F or Cl. For example, chloroaryl and fluoroaryl are suitable halogenated aryl groups.

[0019] In specific embodiments when at least one X 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.

[0020] Examples of suitable alkyl groups for X, R^ and R^ include methyl, ethyl, propyl (e.g. iso-propyl and / or n-propyl), butyl (e.g. isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g. isopentyl, neopentyl, and / or tert-pentyl), hexyl, 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 cycyloheptyl groups.

[0021] 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.

[0022] In one embodiment, subscript a is 10. In another embodiment, subscript a is 12. In one embodiment when subscript a is 10 (and thus subscript b is also 10), at least one, alternatively 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 are halogen atoms. In one embodiment when subscript a is 12 (and thus subscript b is also 12), at least one, alternatively 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 are halogen atoms. In yet other embodiments, regardless of whether subscript a is 10 or 12, each X is other than a halogen atom.

[0023] The catalytically active salt further comprises at least one cation. The catalytically active salt comprises a number of cations to balance the charge associated with the number of dianions. For example, if the catalytically active salt comprises one dianion, then the catalytically active salt may comprise two cations. When the catalytically active salt comprises two dianions, then the catalytically active salt may comprise four cations. At least one cation, alternatively all of the cations, in the catalytically active salt comprise a silylium cation having at least one silicon-bonded halogen atom. When the catalytically active salt comprises more than one cation, eachcation may be independently selected. The catalytically active salt may comprise two or more cations that are different from one another by structure, e.g. the number of silicon-bonded halogen atoms or other substituents. For purposes of clarity, at least one cation is referred to herein as “silylium cation,” which applies to at least one cation, alternatively all cations, in the catalytically active salt.

[0024] In certain embodiments, the silylium cation includes at least one silicon-bonded halogen atom and optionally one or more silicon-bonded hydrocarbyl groups, and optionally one or more silicon-bonded hydrogen atoms, the total number of silicon-bonded groups or atoms being three. Thus, if the silylium cation includes both a silicon-bonded hydrocarbyl group and a silicon-bonded hydrogen atom, the silylium cation would have but one silicon-bonded halogen atom. When the silylium cation includes two silicon-bonded halogen atoms, the silylium cation includes only one silicon-bonded hydrocarbyl group or hydrogen atom. Specific examples of hydrocarbyl groups and halogen atoms are described above.

[0025] In one embodiment, the silylium cation has the general formula [SiR4xQy]+, wherein each R^ is independently selected from hydrocarbyl groups and H, each Q is an independently selected halogen atom, y ≥ 1, x>0, and x + y = 3.

[0026] In this or another embodiment, the silylium cation has the formula [SiR52Q]+, where each R^ is independently selected alkyl or aryl group, and Q is a halogen atom.

[0027] In this or another embodiment, the silylium cation has the formula [SiR62Cl]+, where each R6 is an independently selected alkyl group having from 1 to 8 carbon atoms or aryl group having from 6 to 10 carbon atoms. Examples of alkyl groups for R6 include methyl, ethyl, propyl (e.g. iso-propyl and / or n-propyl), butyl (e.g. isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g. isopentyl, neopentyl, and / or tert-pentyl), hexyl, as well as branched saturated hydrocarbon groups having from 6 to 8 carbon atoms. Examples of suitable non-conjugated cyclic groups (i.e., cycloalkyl groups) include cyclobutyl, cyclohexyl, and cycyloheptyl groups. Examples of aryl groups for R6 include phenyl, tolyl, xylyl, naphthyl, benzyl, and dimethyl phenyl.

[0028] In this or another embodiment, the silylium cation has the formula [SiR6Cl2]+, where each R6is an independently selected and defined above.

[0029] In this or another embodiment, the silylium cation has the formula [SiCl3]+.

[0030] Because the silylium cation has only three substituents (represented initially by R^ and Q above, where subscripts x and y sum to 3), and is highly Lewis acidic, the silylium cation may optionally be associated with another molecule. For example, in certain embodiments, the silylium cation, or the catalytically active salt, may be associated with a hydrocarbon, a silane compound, or a molecule having the general formula Z-O-Z, where each Z is independentlyselected from H, a silyl group, and a substituted or unsubstituted hydrocarbyl group, which may also include one or more heteroatoms. Suitable hydrocarbyl groups Z include any of those described above for X, but optionally further including one or more heteroatoms selected from O, N, and S. Depending on a selection of X in such embodiments, the molecule may be a glycol ether or derivative thereof.

[0031] Silyl groups are known in the art and comprise at least one silicon atom. When Z is a silyl group, typically a silicon atom of the silyl group is bonded to oxygen in the molecule. The silyl group may be, for example, a triorganosilyl group, e.g. (CH3)3Si-, and / or a diorganosilyl group, e.g. -(CH3)2Si-. Alternatively, the silyl group may comprise more than one silicon atom. For example, the silyl group may be a siloxy group. When the silyl group is a siloxy group, the siloxy group is typically free from T siloxy units and Q siloxy units.

[0032] When Z is the silyl group or the substituted or unsubstituted hydrocarbyl group, each Z may be linked together such that the molecule represented by the general formula Z-O-Z is cyclic or a ring structure. As but one example, the molecule represented by the general formula Z-O-Z can be tetrahydrofuran (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).

[0033] In another 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, 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 would be suitable as the hydrocarbon as the molecule as hexene, i.e., notin monovalent form. Any of the groups above for X could be rewritten as H-X for the hydrocarbon. Specific examples of such hydrocarbons, for example, include alkanes such as butane, pentane, hexane, heptane, octane, nonane, decane, etc., arenes such as benzene, toluene, xylene, naphthene, etc.

[0034] 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 hydrocarbon comprises at least one unsaturated moiety, the hydrocarbon may be an alkene, an alkyne, an arene, etc.

[0035] As described above, the catalytically active salt has excellent catalytic properties and can be used in myriad reactions, typically involving silanes and / or organosilicon compounds. The catalytically active salt can be prepared directly and utilized as a discrete catalyst, or can be formed in situ during a reaction from a pre-catalyst. In one embodiment, the catalytically activecatalyst is formed in situ in the presence of a halosilane compound. In such embodiments, a molecule of the halosilane compound may become the silylium cation of the catalytically active salt.

[0036] Exemplary examples of the pre-catalyst that can be utilized to prepare the catalytically active salt in situ include (H)2[B12Cl12]·6(H2O), (H)2[B-|2Br-|2] ‘6(1^0), (H)2[B12I12]·6(H2O), (H)2[B12CI11Br]-6(H2O), (H)2[B1oCI1o]-6(H20), (H)2[B1oBr1o]-6(H20), (H)2[B12CI11(OH)]-6(H2O), (H)2[B12Fi2]-6(H2O)I(H)2[Bi2Cl9(OH)3]-6(H2O), H[Et3Si][B12Cl9(OH)3]·6(H2O), [Et3Si]2[B12Cl12], H[Et3Si][B12Br12], H[Et3Si][B12CI12], [Et3Si]2[B12Br12], [Et3Si]2[B12I12], [Et3Si]2[B12Cl11Br],, [Et3Si]2[B10Cl10], [Et3Si]2[B1oBr1o], [Et3Si]2[B12F12], [C6H7]2[B12Cl12], H[C6H7][B12Cl12],, [Et3Si]2[Bl2Cl9(OSiEt3)3], [Et3Si]2[B12Cl11(OSiEt3)],, [Et3Si]2[B12H12], 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 subscripts a and b in the dianion present in these specific examples.

[0037] The exemplary examples of the pre-catalyst above include both hydrated (or “wet”) and non-hydrated (or “dry”) species. As described below, the number of water molecules shown is representative and may vary. In addition, in addition to or in lieu of water, other ZOZ molecules may be present, where each Z is independently a hydrocarbyl group or H. Thus, ZOZ molecules include water, alcohols, and ethers. The “wet” form of the pre-catalyst is any species including ZOZ molecule(s), and the dry version is free from such ZOZ molecules. In view of the description above, one of skill in the art understands how water can be replaced with other ZOZ molecules, such as alcohols or, for example, THF (when each Z is a hydrocarbyl group linked together to form a ring structure).

[0038] In specific embodiments, the pre-catalyst comprises the hydronium salt of the dianion, rather than the catalytically active salt. As one example, the counterion to the dianion can simply be two protons (H+). The boron cluster is extremely stable, and weak- or noncoordinating. Because the boron cluster is substantially weak- or 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 ZOZ molecules. Typically, the pre-catalyst (B1) in hydrated form cannot be completely dried to become free of ZOZ molecules (like water) by traditional means (e.g., heating under vacuum). Generally, even after drying excess water under vacuum, from two to six or more ZOZ molecules may remain associated with the boron cluster.

[0039] 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 despitethe 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 to be delocalized.Representation Representation"Detailed"Representation

[0040] In the method of the subject disclosure, either the hydrated or non-hydrated versions of the pre-catalyst may be utilized. The hydrated forms of the pre-catalyst can be converted to the dry or non-hydrated forms via the methods described herein. The hydrated forms of the pre-catalyst can be converted to the dry or non-hydrated forms via the methods described herein and in co-pending application number 63 / 716,231 filed on 4 November 2024, which is incorporated by reference herein.

[0041] By way of example, because the cation, e.g. the proton, associated with the dianion of the precatalyst 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 and H2. Two silyliums can then react with water to form a disiloxane, regenerating two protons. As the waters 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 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 HCl gas are prepared by drying rather than silylium and H2.

[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 only ever very weakly coordinated to the boron cluster and these compounds should be seen as mostly ionic. The silylium salt depicted above is an alternative dry form of the pre-catalyst, and does notrepresent the catalytically active salt.

[0043] In certain embodiments, the catalytically active salt is capable of coupling an arene compound to a silicon atom of a hydridosilane compound, as described herein and in co-pending application number 63 / 716,231 filed on 4 November 2024, which is incorporated by reference herein

[0044] By way of example, in one embodiment, the hydridosilane has the formula HSiQ3, where each Q is an individually selected halogen atom as described above. In this or a different embodiment, the hydridosilane has the formula R7x’Hy’SiQz’, where R7is an alkyl group having from 1 to 4 carbon atoms, each Q is an individually selected halogen atom; and each of subscripts x’, y’, and z’ are independently 1 or 2, subject to the proviso that x’+y’+z’=4. Examples of suitable alkyl groups for R7include methyl, ethyl, propyl (e.g. iso-propyl and / or n-propyl), butyl (e.g. isobutyl, n-butyl, tert-butyl, and / or sec-butyl). Each Q is independently selected and defined above.

[0045] In one sub-embodiment, subscript y is 1. In one such sub-embodiment, subscript x is 1, and subscript z is 2 such that the hydridosilane has the formula R7HSiQ2. One specific example of the hydridosilane when R7is methyl and each Q is Cl is methyldichlorosilane. In another such sub-embodiment, subscript x is 2, and subscript z is 1 such that the hydridosilane has the formula R72HSiQ. One specific example of the hydridosilane when each R7is methyl and Q is Cl is dimethylchlorosilane.

[0046] In another sub-embodiment, subscript y is 2. In one such sub-embodiment, subscript x is 1, and subscript z is 1 such that the hydridosilane has the formula R7H2SiQ. One specific example of the hydridosilane when R7is methyl and Q is Cl is methylchlorosilane.

[0047] One exemplary example of the reaction mechanism for coupling the arene compound to the hydridosilane is below (where Me indicates methyl, and Ph indicates phenyl), and where the Active Cl-bearing catalyst is one species of the catalytically active salt of this disclosure:Active Cl-bearing catalyst

[0048] In this specific example, the arene compound is benzene, and each silylium cation is [SiMeCl2]+as a result of the hydridosilane being MeSiHCl2, with one of skill in the art appreciating how different silylium cations would result from different hydridosilanes. The silylium cation binds to benzene, breaking the aromaticity to form species D’ transiently. This species D’ can be viewed as benzene bearing a silylium, 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 catalytically active salt (and regain the aromaticity), closing the catalytic cycle. As a result, the catalytically active salt 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.

[0049] Another example of the reaction mechanism for coupling the arene compound to the hydridosilane is below (where Ph indicates phenyl):

[0050] In this specific example, the arene compound is benzene, and each silylium cation is [SiCl3]+as a result of the hydridosilane being HSiCl3. The silylium cation binds to benzene, breaking the aromaticity to form species D’ transiently. This species D’ can be viewed as benzene bearing a silylium, but also as a silylated benzene that has been protonated. The same description above relating species D’ also applies to this alternative mechanism, even though the species of silylated benzene compound indicated by species D’ is slightly different between each pathway.

[0051] This disclosure also provides use of the catalytically active salt in facilitating the coupling of an arene compound to a hydridosilane.

[0052] In these or other embodiments, the catalytically active salt is capable of facilitating the exchange of one silicon-bonded alkyl group a first silane molecule with a silicon-bonded halogen atom of a second silane molecule, as described herein and in co-pending application number 63 / 716,231 filed on 4 November 2024, which is incorporated by reference herein.

[0053] The first silane molecule and the second silane molecule may have the same structure, or may be different from one another. For example, the first silane molecule may be free from silicon-bonded halogen atoms, in which case the second silane molecule includes at least one silicon-bonded halogen atom.

[0054] For example, as described herein and in co-pending application number 63 / 716,231 filed on 4 November 2024, which is incorporated by reference herein, the following silicon-bonded group exchange was demonstrated with the catalytically active salt:Catalytically-active saltJCatalytically-active saltCatalytically-active saltCatalytically-active saltMe2SiCl2

[0055] One exemplary example of the reaction mechanism for preparing one species of the catalytically active salt for exchanging one silicon-bonded alkyl group a first silane molecule with a silicon-bonded halogen atom of a second silane molecule is below (where Me indicates methyl, and Et indicates ethyl), and where the Active Cl-bearing catalyst is one species of the catalytically active salt of this disclosure:Non Cl-bearing Active Cl-bearing catalyst pre-catalystSiEt3abstracts Cl group - generates active Cl-bearing silylium

[0056] One example mechanism for exchanging one silicon-bonded alkyl group a first silane molecule with a silicon-bonded halogen atom of a second silane molecule based on the particular species of catalytically active salt above is below:

[0057] In this specific example, the silylium cation is [SiMe2CI]+as a result of the first silane molecule being Me2SiCl2, with one of skill in the art appreciating how different silylium cation species would result from different silane molecules or halosilanes. The silylium cation facilitates the exchange of a methyl group to give MesSiCI via methyl group exchange. The newly formed MeSiCl2+containing catalyst abstracts the Cl, ultimately forming MeSiCl3and regenerating the starting catalytically active salt. Since in theory such Me / CI transfer steps may be reversible and may differ depending on the composition of the silane molecule(s) utilized, one of skill in the art can appreciate how the composition of the organosilicon compound can be modulated to obtain the desired target compound after methyl group / chlorine atom exchange. The extent of the reaction may be limited by thermodynamics, but can be driven by removal of either the reactants or products by means such as, but not limited to, distillation, etc.

[0058] This disclosure also provides use of the catalytically active salt in facilitating the exchange of one silicon-bonded alkyl group of a first silane molecule with a silicon-bonded halogen atom of a second silane molecule

[0059] The present invention also provides a composition comprising the catalytically active salt and at least one halosilane compound. The at least one halosilane compound is not limited.

[0060] 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.

[0061] 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.) andutilized as received.

[0062] 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. In the Tables below, “C.” prior to identification of each Component (B) indicates a Comparative Component (B).

[0063] In each of the Examples, the catalyst (B) is prepared in situ from a pre-catalyst. Thus, each component (B) is referred to below as a Pre-Catalyst, with the corresponding catalyst being prepared in situ in each Practical Example.

[0064] Table 1: Materials Utilized and SourcesSynthesis ExamplesSynthesis Example 1

[0065] 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 awater-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 mixture 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 viaNMR spectroscopy. When the reaction was complete, the suspension 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%).

[0066] 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 in a concentrated solution. To the concentrated solution was added DI water (10 mL) to give a diluted solution, and the diluted solution was again concentrated using a rotary evaporator to a volume of ca. 5 mL. The concentration step was repeated one more time to give a solution. 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 in a suspension. 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.spectroscopy confirmed the identity of the isolated white solid as Cs2[B12Cl12] 73% yield.

[0067] 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 to give a solution. 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.

[0068] Synthesis Example 2: [Et3Si]2[B12Cl12]

[0069] In an argon-filled glovebox, to (H)2[B-|2Cli2]‘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). The reaction mixture was heated at 80 °C for 4 h resulting in vigorous evolution of gas. Once the bubbling had stoppedand 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-d6 and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et3Si·C6D6]2[B12Cl12].

[0070] Synthesis Example 3: (H)2[B12Br12]·6(H2O)

[0071] 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). 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. 11B 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 by1H,13C, and11B NMR spectroscopy in acetone-d6, and by high-resolution mass spectrometry (HRMS), were consistent with [Et3NH]2[B12Br12].

[0072] 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 give a mixture. To the mixture 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 wasfiltered and the retentate was washed on the filter with cold water (5 mL) and dried under vacuum at 50 °C.

[0073] (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[B-|2Br-|21’6(H2O).

[0074] Synthesis Example 4: [Et3Si]2[B12Br12]

[0075] 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) 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].

[0076] Synthesis Example 5: (H)2[B12I12]·6(H2O)

[0077] 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 give 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 ^B NMR spectra were consistent with the formation of (H)2[B12I12]·6(H2O).

[0078] Synthesis Example 6: [Et3Si]2[B12I12]

[0079] 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 thereaction mixture 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.

[0080] Synthesis Example 7: (H)2[B12Cl11Br]·6(H2O)

[0081] 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 components 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 (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 (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 NaOCl in water (~5%, 128mL, 86.2 mmol) was added dropwise and the mixture was heated at the reflux temperature overnight. HRMS and ^B NMR spectroscopy showed conversion to the desired product. The solution was cooled to room temperature and to the solution was added [EtsNHJCI (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 [HNEtsJ. The material was redissolved in MeOH and to the solution was added (H+) ion exchange resin (6 g) and allowed to stand overnight. Themixture was again filtered and dried to give a tan solid that was free from residual [EtsNH] as determined by NMR spectroscopy. (H)2[B-|2Cli2B’6(1^0), 1.56 g, 62%).

[0082] Synthesis Example 8: [Et3Si]2[B12Cl11Br]

[0083] 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[B-| 2^11 Br] (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, 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.

[0084] Synthesis Example 9: (H)2[B10Cl10]·6(H2O)

[0085] To a solution of Na2[B10H10] (2 g, 12.2 mmol) in H2O (20 mL) was added concentrated HCl (10 mL). With stirring, a solution of NaOCl in water (6%, 302 mL, 243 mmol) was added to give a mixture. The mixture was heated at the reflux temperature overnight. 1H and 11 B NMR spectra of the solution were consistent with the perchlorination of the cage.

[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 by 1H NMR spectroscopy showed that residual [EtsNH] 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 [EtsNH] and so the solution was filtered and dried in vacuo affording 2.04 g of (H)2[B-|QCI-|O]’6(H20). The retained filtrate was free from [Et3NH] but was treated with (H+) ion exchange resin to ensure the completeremoval 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 4.78 g (68%).

[0087] Synthesis Example 10: [Et3Si]2[B10Cl10]

[0088] In an argon-filled glovebox, (H)2[B10Cl10]·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-d6 and the solution was analyzed by NMR spectroscopy, revealing the formation of [Et3Si·C6D6]2[B10Cl10]. Synthesis Example 11: (H)2[B-|oBr-|ol‘6(H20)

[0089] 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 NaOCl 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%).

[0090] Synthesis Example 12: [Et3Si]2[B10Br10]

[0091] In an argon-filled glovebox, (H)2[B-|oBr-|ol‘6(H20) (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 monitoringthe 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 dried under vacuum. The target [Et3Si]2[B10Br10] was obtained as a white crystalline solid (282 mg, 77% yield).

[0092] Synthesis Example 13: (H)2[B12Cl11(OH)]·6(H2O)

[0093] 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 form a mixture. The mixture was heated at 90 °C for 5 h. Conversion to [B12H11(OH)]2−was confirmed by11B 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.

[0094] 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 concentrated under vacuum to give a white residue, which was recrystallized from hot water, giving 7.4 g of a white crystalline solid. The ^B NMR spectra were consistent with the [B-|2CI-| -|(OH)]2“ dianion with a low concentration of an impurity.

[0095] 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%).

[0096] Synthesis Example 14: [Et3Si]2[B12F12]

[0097] 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). In an argon filled glovebox, to 388 mg of the (H)2[B12F12]·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 °C, and allowed to stand at that temperature for 1 h. During this time, rapid evolution of gas wasobserved. 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 spectroscopy, revealing the formation of [Et3Si·C6D6]2[B12F12].

[0098] Synthesis Example 15: [C6H7]2[B12Cl12]

[0099] To a stirred suspension of [Et3Si]2[B12Cl12] (as prepared in Synthesis Example 2) (307.9 mg, 0.392 mmol) in benzene (3 mL) in a 20 mL glass vial was added trifluoromethanesulfonic acid (139 µL, 235 mg, 1.57 mmol, 4 equiv) to give a mixture, 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 × 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[B12Cl12].

[0100] Synthesis Example 16: (H)2[B12Cl9(OH)3]·6(H2O)

[0101] A 500 mL flask with a stir bar was charged with Cs2[B-|2H-|2] (6 g, 15 mmol). The flask was cooled in an ice bath and aqueous H2SO4(53% v / v, 120 mL) was added dropwise with vigorous 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.11B NMR showed conversion to the [B12(OH)3H9] 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%.

[0102] 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 µL, 3.55 mmol, 3.5 equiv). The mixture wasstirred at 70 °C overnight.11B NMR showed full conversion to the [B12Cl9(OSiMe3)3] dianion.

[0103] [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 SiMe3groups. The filtrate was dried in vacuo to give (H)2[B12Cl9(OH)3]·6(H2O) as a tannish solid (357 mg).

[0104] Synthesis Example 17: (H)2[B12H12]·6(H2O)

[0105] A 30 wt.% solution of (H)2[B-|2H-|2]inwater was concentrated under vacuum at 30 °C to give a deliquescent white solid (H)2[B-|2H-|2]‘6(H2O).

[0106] Synthesis Example 18: [Et3Si]2[B12Cl9(OSiEt3)3]

[0107] In an argon purged glovebox, in a 20 mL scintillation vial was weighed [H]2[B12Cl9(OH)3]·6H2O (140 mg) and Et3SiH (334.8 mg) was added at once along with benzene (1.5 mL) to give a reaction mixture. The reaction mixture in the open reaction vessel was warmed up slowly to 80 °C, leading to vigorous bubbling. The reaction mixture was heated at that temperature for 1 hour, after which time additional benzene (2.0 mL) and Et3SiH (200 mg) were added and the reaction mixture further heated at 80 °C for 1 hour. After this time, bubbling had fully subsided. The supernatant was removed via pipet, and heptane (4 mL) was added to the solids to form a mixture. This mixture was warmed up to 80 °C after which the heptane was removed and the solid was dried in vacuo yielding 200 mg of the title compound as a tan solid.

[0108] Synthesis Example 19: [Et3Si]2[B12Cl11(OSiEt3)]

[0109] In an argon purged glovebox, in a 40 mL scintillation vial, [H]2[B12Cl11(OH)]·6H2O (248 mg) was weighed and Et3SiH (624 mg) was added at once along with benzene (1.5 mL) to form a mixture. The mixture was heated to 60 °C for 3h, until the mixture had completely transformed to a brown oil. Heptane (1 mL) was layered on the mixture to form a reaction mixture, and the reaction mixture left to stand at room temperature overnight. The supernatant was removed, then the liquid stripped at 60 °C under vacuum, yielding a sticky solid. Heptane (2 mL) was added, and the mixture heated to 60 °C for 1h. The hot supernatant was removed, and the sampled dried under vacuum at 60 °C, leading to the formation of the title compound as a pale brown solid (200 mg). A small amount of the sample was dissolved in 0.5 mL of a mixture of ortho-difluorobenzene and CgDg (4:1 ratio) and analyzed by multinuclear NMR spectroscopy, confirming the formation of the desired silylium salt.

[0110] Synthesis Example 20: [Et3Si]2[B12H12]

[0111] In an argon purged glovebox, in a 40 mL scintillation vial was weighed [H]2[B-|2H-|2]‘2H2O (192 mg) as a white solid and EtsSiH (1.24 g) was added at once along with benzene (1.5 mL). The reaction mixture was left standing at room temperature for 6 hours after which time a yellow solid had formed. The supernatant was removed, then the solids were rinsed with benzene (4 mL), then heptane (4 mL) and then dried in vacuo yielding 400 mg of the title compound as a yellow solid which was used without further purification.

[0112] Practical Examples 1-31 demonstrate preparation and use of the catalytically active salt in coupling an arene compound (benzene) to a hydridosilane.

[0113] General Procedure 1 for Examples 1-20:

[0114] 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 Pre-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 the heat was turned off and the sample was allowed to cool to room temperature. 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 the heat was turned off and the sample was allowed to cool to room temperature. 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 allowed to cool to room temperature. An aliquot of this sample was dissolved in C6D6(0.5 g) and analyzed by multinuclear NMR spectroscopy (1H,29Si). Table 2 below shows the identity and the amount of each Pre-Catalyst and reactant utilized in Examples 1-20. Table 3 shows the corresponding yields associated with product distribution.

[0115] Table 2: Examples 1-20:

[0116] Table 3: Product distribution for Examples 1-20 (yields in %):

[0117] General Procedure 2 for Examples 21-31:

[0118] 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 thattemperature 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 CgDg (0.5 g) and analyzed by multinuclear NMR spectroscopy (^H, 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 CgDg (0.5 g) and analyzed by multinuclear NMR spectroscopy (^H, 29si). Table 4 below shows the amount of each Pre-Catalyst and reactant utilized in Examples 21-31. Table 5 shows the corresponding yields associated with product distribution.

[0119] Table 4: Examples 21-31:

[0120] Table 5: Product distribution for each of Examples 21-31 (yields in %)

[0121] General Procedure 3 for Examples 1-20:CatalystMe3SiCI + MeSiCI3- < - ► Me4Si + Me2SiCI22h, 120 °C2h, 150 °C2h, 180 °C

[0122] In a nitrogen filled glovebox, each species of Pre-Catalyst as prepared or obtained above and identified below (=30mg) was weighed in a glass vial and transferred to a stainless steel reactor. The reactants (defined below) were weighed in a glass vial, and the pre-catalyst-containing vial was rinsed with the reactants and this mixture was also added to the stainless steel reactor. Table 6 below shows the amount of each Pre-Catalyst and reactants utilized in Examples 32-51.

[0123] 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 (0.1 g) of this sample was dissolved in C5D5 (0.8 g) and analyzed by multinuclear NMR spectroscopy (^H, 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 (0.1 g) of this sample was dissolved in CgDg (0.8 g) and analyzed by multinuclear NMR spectroscopy (”*H, 29gi). 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 (0.1 g) of this sample was dissolved in CgOg (0.8 g) and analyzed by multinuclear NMR spectroscopy (”*H, 29sj). Table 7 shows the corresponding yields associated with product distribution.

[0124] Table 6: Examples 32-51:

[0125] Table 7: Product distribution for each of Examples 32-51 (yields in %):

[0126] General Procedure 4 for Examples 52-71:CatalystMeSiCl3→ Me4Si + Me3SiCl + Me2SiCl22h, 120 °C2h, 150 °C2h, 180 °C

[0127] General Procedure 4 was the same as General Procedure 3, except only MeSiCl3 was utilized as a reactant, as shown above. Table 8 below shows the amount of each PreCatalyst and reactant utilized in Examples 52-71. Table 9 shows the corresponding yield of each product.

[0128] Table 8: Examples 52-71:

[0129] Table 9: Product distribution for Examples 52-71 (yields in %):

[0130] General Procedure 5 for Examples 72-74:CatalystMe4Si + SiCl4- ►2h, 120 °C2h, 150 °C2h, 180 °C

[0131] General Procedure 5 was the same as General Procedure 3, except Me4Si and SiCl4 were utilized as reactants, as shown above. Table 10 below shows the amount of each Pre-Catalyst and reactant utilized in Examples 72-74. Table 11 shows the corresponding yield of each product.

[0132] Table 10: Examples 72-74:

[0133] Table 11: Product distribution Examples 41-43 (yields in %):

[0134] General Procedure 6 for Example 75:CatalystMe4Si + MeSiCI3- ► Me3SiCI + Me2SiCI22h, 120 °C2h, 150 °C2h, 180 °C

[0135] General Procedure 6 was the same as General Procedure 3, except Me4Si and MeSiCl3 were utilized as reactants, as shown above. Table 8 below shows the amount of each Pre-Catalyst and reactant utilized in Example 75. Table 12 shows the corresponding yield of eachproduct.

[0136] Table 12: Example 75:

[0137] Table 13: Product distribution for Example 75 (yields in %).

[0138] General Procedure 7 for Example 76-78:CatalystMe2SiCl2- Me3SiCI + MeSiCI32h, 150 °C

[0139] General Procedure 7 was the same as General Procedure 3, except Me2SiCl2 was utilized as the reactant, as shown above. Table 14 below shows the identification and the amount of each Pre-Catalyst and reactant utilized in Examples 76-78. Table 15 shows the corresponding yield of each product.

[0140] Table 14: Example 76-78:

[0141] Table 15: Product distribution for Comparative Examples 45-47 and Comparative Example 10 (yields in %).

Claims

CLAIMSWhat is claimed is:

1. A catalytically active salt, comprising:at least one boron cluster dianion; andat least one cation;wherein the cation comprises a silylium cation having at least one silicon-bonded halogen atom.

2. The catalytically active salt of claim 1, wherein the silylium cation has the general formula [SiR4xQy]+, wherein each R^ is independently selected from hydrocarbyl groups and H, each Q is an independently selected halogen atom, y ≥ 1, x>0, and x + y = 3.

3. The catalytically active salt of claim 1 or 2, wherein the silylium cation has the formula [SiR^2Q]+, where each R^ is independently selected alkyl or aryl group, and Q is a halogen atom.

4. The catalytically active salt of claim 1 or 2, wherein the silylium cation has the formula [SiR62Cl]+, where each R® is an independently selected alkyl group having from 1 to 8 carbon atoms or aryl group having from 6 to 10 carbon atoms.

5. The catalytically active salt of claim 1 or 2, wherein the silylium cation has the formula [SiR®Q2]+, where each R® is an independently selected alkyl group having from 1 to 8 carbon atoms or aryl group having from 6 to 10 carbon atoms, and each Q is an independently selected halogen atom.

6. The catalytically active salt of claim 1 or 2, wherein the silylium cation has the formula [SiQ3]+, where each Q is independently selected and defined above.

7. The catalytically active salt of any one preceding claim, wherein the boron cluster dianion has the general formula (BaXb)2-, where subscript a is 10 or 12, subscript b=a, wherein each X is independently selected from halogen atoms; H; hydrocarbyl groups; -SiR^ groups, where each R^ is independently a hydrocarbyl group, H, or a halogen atom; -OR^ groups, where each R^ is independently H, an alkyl group, or a silyl group; methanesulfonyloxy (mesyloxy) groups, tosyloxy groups, triflyloxy groups, nitro-phenylsulfonyloxy (nosyloxy)groups, bromo-phenylsulfonyloxy (brosyloxy) groups, and 0C(0)R3 groups, where R^ is an alkyl group.

8. The catalytically active salt of any one preceding claim formed in situ in the presence of a halosilane compound.

9. The catalytically active salt of any one preceding claim capable of coupling an arene compound to a silicon atom of a hydridosilane compound.

10. The catalytically active salt of any one preceding claim capable of facilitating the exchange of one silicon-bonded alkyl group a first silane molecule with a silicon-bonded halogen atom of a second silane molecule.

11. The catalytically active salt of any one preceding claim, wherein the boron cluster dianion comprises nine or more halogen atoms.

12. The catalytically active salt of any one preceding claim, wherein the atoms of the boron cluster dianion are arranged in a closo-cage structural arrangement.

13. The catalytically active salt of any one preceding claim, comprising two silylium cations each having at least one silicon-bonded halogen atom and a charge of +1.

14. A composition comprising the catalytically active salt of any one preceding claim and at least one halosilane compound.

15. Use of the catalytically active salt of any one preceding claim to couple an arene compound to a silicon atom of a hydridosilane compound.

16. Use of the catalytically active salt of any one preceding claim to facilitate the exchange of one silicon-bonded alkyl group of a first silane molecule with a silicon-bonded halogen atom of a second silane molecule.

Images