title: Asymmetric Michael addition of alpha-hydroxyketones to nitroolefins catalyzed by chiral diamine.
abstract: [reaction: see text] The regio-, stereo-, and enantioselective direct Michael addition of alpha-hydroxyketones to beta-arylnitroolefins catalyzed by N-iPr-2,2'-bipyrrolidine is described. The formation of an internal hydrogen bond between the OH group of alpha-hydoxyacetone and the tertiary nitrogen of the catalyst leads to the formation of a rigid cis enamine intermediate that explains the inversion of the expected diastereoselectivity and the very high ee's.
authors.affiliation: Chimie Organique, Sciences II, University of Geneva, Quai Ernest Ansermet, CH-1211, Geneva, Switzerland.
authors.forename: Olivier
authors.initials: O
authors.lastname: Andrey
authors.forename: Alexandre
authors.initials: A
authors.lastname: Alexakis
authors.forename: Gérald
authors.initials: G
authors.lastname: Bernardinelli