Metal-Free Catalytic C–Si Bond Formation in an Aqueous Medium. Enantioselective NHC-Catalyzed Silyl Conjugate Additions to Cyclic and Acyclic α, β-Unsaturated …

JM O'Brien, AH Hoveyda

Index: Dabrowski, Jennifer A.; Gao, Fang; Hoveyda, Amir H. Journal of the American Chemical Society, 2011 , vol. 133, # 13 p. 4778 - 4781

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Citation Number: 69

Abstract

A metal-free method for enantioselective conjugate addition of a dimethylphenylsilyl group to α, β-unsaturated carbonyls is reported. Transformations are catalyzed by a chiral N- heterocyclic carbene (NHC), performed in an aqueous solution (3: 1 mixture of water and tetrahydrofuran) and are operationally simpler to perform than the NHC–Cu-catalyzed variant. The chiral catalyst is generated from an enantiomerically pure imidazolinium salt ( ...