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Hydrosilylation, also called catalytic hydrosilation, describes the addition of Si-H bonds across unsaturated bonds.〔"Hydrosilylation A Comprehensive Review on Recent Advances" B. Marciniec (ed.), Advances in Silicon Science, Springer Science, 2009. 〕 Ordinarily the reaction is conducted catalytically and usually the substrates are unsaturated organic compounds. Alkenes and alkynes give alkyl and vinyl silanes; aldehydes and ketones give silyl ethers. The process was first reported in academic literature in 1947. Hydrosilylation has been called the "most important application of platinum in homogeneous catalysis." ==Scope and mechanism== The catalytic transformation represents an important method for preparing organosilicon compounds. An idealized transformation is illustrated by the addition of triethylsilane to diphenylacetylene:〔James L. Fry, Ronald J. Rahaim Jr., Robert E. Maleczka Jr. "Triethylsilane", ''Encyclopedia of Reagents for Organic Synthesis'', John Wiley & Sons, 2007. 〕 :Et3SiH + PhC≡CPh → Et3Si(Ph)C=CH(Ph) The reaction is related mechanistically to hydrogenation, and similar catalysts are sometimes employed for the two catalytic processes. Popular industrial catalysts are "Speier's catalyst," H2PtCl6, and Karstedt’s catalyst (an alkene-stabilized platinum(0) catalyst.〔C. Elschenbroich, ''Organometallics'' (2006) Wiley and Sons-VCH: Weinheim. ISBN 978-3-527-29390-2〕 One prevalent mechanism, called the Chalk-Harrod mechanism, assumes an intermediate metal complex that contains a hydride, a silyl ligand (R3Si), and the alkene substrate. The reaction usually produces anti-Markovnikov addition alkane, i.e., silicon on the terminal carbon.〔 Variations of the Chalk-Harrod mechanism. Some cases involve insertion of alkene into M-Si bond followed by reductive elimination. In certain cases, hydrosilylation results in vinyl or allylic silanes resulting from beta-hydride elimination.〔Troegel, D.; Stohrer, J., "Recent advances and actual challenges in late transition metal catalyzed hydrosilylation of olefins from an industrial point of view", Coord. Chem. Rev. 2011, 255, 1440-1459. 〕 These reactions can also be catalyzed using nanomaterial-based catalysts. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hydrosilylation」の詳細全文を読む スポンサード リンク
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