Formation of Quaternary Chiral Centers by N??Heterocyclic Carbene–Cu??Catalyzed Asymmetric Conjugate Addition Reactions with Grignard Reagents on …

S Kehrli, D Martin, D Rix, M Mauduit…

Index: Kehrli, Stefan; Martin, David; Rix, Diane; Mauduit, Marc; Alexakis, Alexandre Chemistry - A European Journal, 2010 , vol. 16, # 32 p. 9890 - 9904

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Citation Number: 74

Abstract

Abstract The copper-catalyzed conjugate addition of Grignard reagents to 3-substituted cyclic enones allows the formation of all-carbon chiral quaternary centers. We demonstrate in this article that N-heterocyclic carbenes act as efficient chiral ligands for this transformation. High enantioselectivities (up to 96% ee) could be obtained for a variety of substrates.