Enantioselective organocatalytic conjugate addition of α-nitroacetate to α,β-unsaturated ketones in water

The catalytic enantioselective conjugate addition reaction of alpha-nitroacetate to alpha,beta-unsaturated ketones promoted by chiral bifunctional organocatalysts is described. The treatment of alpha-nitroacetate to alpha,beta-unsaturated ketones under aqueous-phase reaction conditions afforded the corresponding Michael adducts with high enantioselectivity. The conjugate addition adducts are easily converted to chiral delta-keto nitroalkanes and delta-keto esters. (C) 2010 Elsevier Ltd. All rights reserved.