Enantioselectively organocatalytic Michael addition of ketones to alkylidene malonates

J Org Chem. 2007 May 25;72(11):4073-6. doi: 10.1021/jo070070p. Epub 2007 May 3.

Abstract

An organocatalytic asymmetric Michael addition of ketones to alkylidene malonates has been developed. In the presence of 20 mol % of urea 1a or N-(pyrrolidin-2-ylmethyl)trifluoromethanesulfonamide 1j, the reactions of ketones with alkylidene malonates afford the desired Michael adducts in moderate to good yields with good to high enantioselectivities under mild conditions.