Catalytic Asymmetric Michael Reactions of α,β-Unsaturated Ketones with Sulfonyl-Containing Nucleophiles: Chiral Synthesis of (R)-Muscone and (S)-Celery Ketone

An amine worth its salt: A highly enantioselective Michael addition reaction of α,β-unsaturated ketones with the sulfonyl-containing nucleophiles bis(phenylsulfonyl)methane and 1-(phenylsulfonyl)propan-2-one, catalyzed by a chiral primary amine salt, has been developed and gives excellent enantioselectivities (see scheme). The methodology has successfully demonstrated its synthetic utility in the chiral synthesis of (R)-muscone and (S)-celery ketone. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.