1072-14-6Relevant articles and documents
Reaction of allylamine with hexylsilane
Storozhenko,Belyakova,Knyazev,Shutova,Khromykh,Starikova,Chernyshev
, p. 220 - 224 (2006)
The reaction of hexylsilane with allylamine is accompanied by the liberation of hydrogen and formation of allylaminosilanes and compounds with the Si-Si bond. The hydrosilylation pathway virtually is not realized. The B3LYP/6-311G**calculations show that all the considered reactions are thermodynamically allowed. Pleiades Publishing, Inc., 2006.
Synthesis of hydrosilanes: Via Lewis-base-catalysed reduction of alkoxy silanes with NaBH4
Aoyagi, Keiya,Ohmori, Yu,Inomata, Koya,Matsumoto, Kazuhiro,Shimada, Shigeru,Sato, Kazuhiko,Nakajima, Yumiko
, p. 5859 - 5862 (2019)
Hydrosilanes were synthesized by reduction of alkoxy silanes with BH3 in the presence of hexamethylphosphoric triamide (HMPA) as a Lewis-base catalyst. The reaction was also achieved using an inexpensive and easily handled hydride source NaBH4, which reacted with EtBr as a sacrificial reagent to form BH3in situ.
Alkenylsilane effects on organotitanium-catalyzed ethylene polymerization. Toward simultaneous polyolefin branch and functional group introduction
Amin, Smruti B.,Marks, Tobin J.
, p. 4506 - 4507 (2006)
The comonomer 5-hexenylsilane is introduced into organotitanium-mediated ethylene polymerizations to produce silane-terminated ethylene/5-hexenylsilane copolymers. The resulting polymers were characterized by 1H and 13C NMR, GPC, and DSC. High activities (up to 107 g polymer/(mol Ti·atm ethylene·h)) and narrow polydispersities are observed in the polymerization/chain transfer process. Ethylene/5-hexenylsilane copolymer molecular weights are found to be inversely proportional to 5-hexenylsilane concentration, supporting a silanolytic chain transfer mechanism. Control experiments indicate that chain transfer mechanism by 5-hexenylsilane is significantly more efficient than that of n-hexylsilane for organotitanium-mediated ethylene polymerization. The present study represents the first case in which a functionalized comonomer is efficiently used to effect both propagation and chain transfer chemistry during olefin polymerization. Copyright
PROCESS FOR THE STEPWISE SYNTHESIS OF SILAHYDROCARBONS
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Page/Page column 73, (2021/12/08)
The invention relates to a process for the stepwise synthesis of silahydrocarbons bearing up to four different organyl substituents at the silicon atom, wherein the process includes at least one step a) of producing a bifunctional hydridochlorosilane by a redistribution reaction, selective chlorination of hydridosilanes with an ether/HCI reagent, or by selective chlorination of hydridosilanes with SiCI4, at least one step b) of submitting a bifunctional hydridochloromonosilane to a hydrosilylation reaction, at least one step c) of hydrogenation of a chloromonosilane, and a step d) in which a silahydrocarbon compound is obtained in a hydrosilylation reaction.
CO Displacement in an Oxidative Addition of Primary Silanes to Rhodium(I)
Biswas, Abhranil,Ellern, Arkady,Sadow, Aaron D.
, (2019/03/11)
The rhodium dicarbonyl {PhB(Ox Me2)2ImMes}Rh(CO)2 (1) and primary silanes react by oxidative addition of a nonpolar Si-H bond and, uniquely, a thermal dissociation of CO. These reactions are reversible, and kinetic measurements model the approach to equilibrium. Thus, 1 and RSiH3 react by oxidative addition at room temperature in the dark, even in CO-Saturated solutions. The oxidative addition reaction is first-Order in both 1 and RSiH3, with rate constants for oxidative addition of PhSiH3 and PhSiD3 revealing kH/kD a 1. The reverse reaction, reductive elimination of Si-H from {PhB(Ox Me2)2ImMes}RhH(SiH2R)CO (2), is also first-Order in [2] and depends on [CO]. The equilibrium concentrations, determined over a 30 °C temperature range, provide ?"H° = a'5.5 ± 0.2 kcal/mol and ?"S° = a'16 ± 1 cal·mol-1K-1 (for 1 a?., 2). The rate laws and activation parameters for oxidative addition (?"Ha§§ = 11 ± 1 kcal·mol-1 and ?"Sa§§ = a'26 ± 3 cal·mol-1·K-1) and reductive elimination (?"Ha§§ = 17 ± 1 kcal·mol-1 and ?"Sa§§ = a'10 ± 3 cal·mol-1K-1), particularly the negative activation entropy for both forward and reverse reactions, suggest the transition state of the rate-Determining step contains {PhB(Ox Me2)2ImMes}Rh(CO)2 and RSiH3. Comparison of a series of primary silanes reveals that oxidative addition of arylsilanes is ca. 5× faster than alkylsilanes, whereas reductive elimination of Rh-Si/Rh-H from alkylsilyl and arylsilyl rhodium(III) occurs with similar rate constants. Thus, the equilibrium constant Ke for oxidative addition of arylsilanes is >1, whereas reductive elimination is favored for alkylsilanes.
MANUFACTURING METHOD OF HYDROSILANE
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Paragraph 0037-0038, (2019/07/13)
PROBLEM TO BE SOLVED: To provide a manufacturing method of hydrosilane capable of manufacturing hydrosilane at good efficiency. SOLUTION: Hydrosilane having a structure represented by the following formula (b) can be manufactured at good efficiency by reacting borohydride and hydrocarbon having a halogen atom and 1 to 20 carbon atoms, and/or a metal salt and further reacting the reaction product with alkoxysilane having a structure represented by the following formula (a) in the presence of triamide phosphate. In the formula (a), R represents a hydrocarbon group having 1 to 20 carbon atoms. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
METHOD FOR PRODUCING HYDROSILANE USING BORANE REDUCTION
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Paragraph 0025, (2018/07/28)
PROBLEM TO BE SOLVED: To provide a method for producing hydrosilane that can efficiently produce the hydrosilane. SOLUTION: In the presence of a Lewis base, a silane having a structure represented by a formula (a) reacts with a borane complex or diborane, to efficiently produce hydrosilane (in the formula (a), R1 is a C1 to C20 hydrocarbon group, or a C1 to C10 acyl group). SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
Structural and mechanistic investigation of a cationic hydrogen-substituted ruthenium silylene catalyst for alkene hydrosilation
Fasulo, Meg E.,Lipke, Mark C.,Tilley, T. Don
, p. 3882 - 3887 (2013/09/23)
The cationic ruthenium silylene complex [Cp*(iPr 3P)Ru(H)2(SiHMes)][CB11H6Br 6], a catalyst for olefin hydrosilations with primary silanes, was isolated and characterized by X-ray crystallography. Relatively strong interactions between the silylene Si atom and Ru-H hydride ligands appear to reflect a highly electrophilic silicon center. The mechanism of olefin hydrosilation was examined by kinetics measurements and other experiments to provide the first experimentally determined mechanism for the catalytic cycle. This mechanism involves a fast, initial addition of the Si-H bond of the silylene complex to the olefin. Subsequent elimination of the product silane produces an unsaturated intermediate, which can be reversibly trapped by olefin or intercepted by the silane substrate. The latter reaction pathway involves activation of the reactant silane by Si-H oxidative addition and α-hydrogen migration to regenerate the key silylene intermediate.
Synthesis and structure of PNP-supported iridium silyl and silylene complexes: Catalytic hydrosilation of alkenes
Calimano, Elisa,Tilley, T. Don
body text, p. 11161 - 11173 (2009/12/05)
Oxidative addition of bulky primary, secondary, and tertiary silanes to PNP (PNP ) [N(2-PiPr2-4-Me-C6H3) 2]-) iridium complexes (PNP)IrH2 and (PNP)Ir(COE) (11) afforded iridium silyl hydride complexes (PNP)Ir(H) (SiRR′R″) (3-8). Addition of 2 equiv of PhSiH3 or (3,5-Me2C6H3)SiH3 to (PNP)IrH 2 or 11 yielded disilyl complexes (PNP)Ir(SiH2R) 2 (R ) Ph (9), 3,5-Me2C6H3 (10)). Hydride abstraction from (PNP)Ir-(H)(SiH2R) (R = Trip (5), Dmp (6)) by [Ph3C][B(C6F5)4] afforded iridium silylene complexes [(PNP)(H)Ir=SiR(H)][B(C6F5) 4] (R ) Trip (12), Dmp (13)) exhibiting downfield 29Si NMR resonances (234 ppm (12), 226 ppm (13)) and downfield 1H NMR resonances for the Si-H group (10.76 ppm (12), 9.76 ppm (13)). Thermally stable disubstituted silylene complexes [(PNP)(H)Ir=SiPh2][A] (A = -B(C 6F5)4 (14), -CB11H 6Br6 (16)) were isolated via hydride abstraction from (PNP)Ir(H)(SiHPh2). The X-ray structure of 16 confirmed sp 2 hybridization at silicon and revealed a short Ir-Si bond of 2.210(2) A. Catalytic hydrosilation of alkenes by hydrogen-substituted silylene complexes [(PNP)(H)Ir=SiMes(H)][B(C6F5) 4] (1) and 14 exhibited anti-Markovnikov regioselectivity with an array of alkene substrates. Addition of H3SiMes to complex 1 afforded [(PNP)(SiH(Mes)(Hex))IrH(SiH2Mes)][B(C6F 5)4] (19), featuring a β-agostic interaction demonstrated by a JSiH of 102 Hz for the N-SiH hydrogen. Similarly, addition of H2SiPh2 to 16 afforded the structurally characterized Ir(V) disilyl complex [(PNP)(SiPh2)Ir(SiPh 2H)(H)2][CB11H6Br6] (20). Complex 20 was found to be catalytically active for the hydrosilation of alkenes, which is consistent with its intermediacy in the catalytic cycle.
Alkenylsilane structure effects on mononuclear and binuclear organotitanium-mediated ethylene polymerization: Scope and mechanism of simultaneous polyolefin branch and functional group introduction
Amin, Smruti B.,Marks, Tobin J.
, p. 2938 - 2953 (2007/10/03)
Alkenylsilanes of varying chain lengths are investigated as simultaneous chain-transfer agents and comonomers in organotitanium-mediated olefin polymerization processes. Ethylene polymerizations were carried out with activated CGCTiMe2 and EBICGCTi2Me4 (CGC = Me2Si(Me4C5)(NtBu); EBICGC = (μ-CH2CH2-3,3′){(η5-indenyl)[1- Me2Si(tBuN)]}2) precatalysts in the presence of allylsilane, 3-butenylsilane, 5-hexenylsilane, and 7-octenylsilane. In the presence of these alkenylsilanes, high polymerization activities (up to 10 7 g of polymer/(mol of Ti-atm ethylene·h)), narrow product copolymer polydispersities, and substantial amounts of long-chain branching are observed. Regardless of Ti nuclearity, alkenylsilane incorporation levels follow the trend C8H15SiH3 6H 11SiH3 ≈ C4H7SiH3 3H5SiH3. Alkenylsilane comonomer incorporation levels are consistently higher for CGCTiMe2-mediated copolymerizations (up to 54%) in comparison with EBICGCTi2Me 4-mediated copolymerizations (up to 32%). The long-chain branching levels as compared to the total branch content follow the trend C 3H5SiH3 4H7SiH 3 ≈ C6H11SiH3 ≈ C 8H15SiH3, with gel permeation chromatography-multi-angle laser light scattering-derived branching ratios (gM) approaching 1.0 for C8H15SiH3. Time-dependent experiments indicate a linear increase of copolymer Mw with increasing polymerization reaction time. This process for producing long-chain branched polyolefins by coupling of an α-olefin with a chain-transfer agent in one comonomer is unprecedented. Under the conditions investigated, alkenylsilanes ranging from C3 to C8 are all efficient chain-transfer agents. Ti nuclearity significantly influences silanolytic chain-transfer processes, with the binuclear system exhibiting a sublinear relationship between Mn and [alkenylsilane]-1 for allylsilane and 3-butenylsilane, and a superlinear relationship between Mn and [alkenylsilane]-1 for 5-hexenylsilane and 7-octenylsilane. For the mononuclear Ti system, alkenylsilanes up to C 6 exhibit a linear relationship between Mn and [alkenylsilane]-1, consistent with a simple silanolytic chain termination mechanism.
