First organocatalyzed asymmetric Michael addition of aldehydes to vinyl sulfones.
[reaction: see text] The first asymmetric direct Michael addition of aldehydes to vinyl sulfones catalyzed by N-iPr-2,2'-bipyrrolidine is described. 1,4-Adducts are obtained in good yields and enantioselectivities. The determination of absolute configuration allowed us to postulate a Si,Si transition state model, as shown previously for nitroolefins.
Mossé
Sarah
S
Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva, Switzerland.
Alexakis
Alexandre
A