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Hydroacylation is a type of organic reaction in which an aldehyde is added over an alkene or alkyne bond. The reaction product is a ketone. The reaction requires a metal catalyst, often rhodium. It is almost invariably practice as an intramolecular reaction. With an alkyne in place of alkenes, the reaction product is an α,β-unsaturated ketone.〔Michael C. Willis ''Transition Metal Catalyzed Alkene and Alkyne Hydroacylation'' Chem. Rev. 2009 〕 : The reaction was discovered as part of a synthetic route to certain prostanoids.〔''Synthetic studies on prostanoids 1 synthesis of methyl 9-oxoprostanoate'' K. Sakai, J. Ide, O. Oda and N. Nakamura Tetrahedron Letters Volume 13, Issue 13, 1972, Pages 1287-1290 〕 The reaction required tin tetrachloride and a stoichiometric amount of Wilkinson's catalyst. An equal amount of a cyclopropane was formed as the result of decarbonylation. : The first catalytic application was reported by Miller in 1976.〔''Transition-Metal-Promoted Aldehyde-Alkene Addition Reactions'' Charles F. Lochow, Roy G. Miller J. Am. Chem. Soc., 1976, 98 (5), pp 1281–1283 〕 In their reaction, treatment of 4-pentenal with Wilkinson's catalyst gave cyclopentanone. In this reaction the solvent was saturated with ethylene. : Another suitable catalyst is the salt Rh(dppe2)ClO4. ==Reaction mechanism== In terms of the reaction mechanism, hydroacylation involves oxidative addition of the aldehydic carbon-hydrogen bond and complexation of the alkene. The order is often unclear. The alkene inserts into either the metal-acyl or the metal-hydride bonds. In the final step, the resulting alkyl-acyl or beta-ketoalkyl-hydride complex undergoes reductive elimination.〔 A competing side-reaction is deinsertion from the acyl metal hydride: :RCH2C(O)MH → RCH2M(CO)H This step can be followed by CO loss and reductive elimination of the alkane. : 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「Hydroacylation」の詳細全文を読む スポンサード リンク
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