Enantioselective conjugate addition of ketones to β-nitrostyrenes catalyzed by 1,2-amino alcohol-derived prolinamides

Various L-prolinamides 14, prepared from L-proline and chiral beta-amino alcohols, are active bifunctional catalysts for the direct nitro-Michael addition of ketones to beta-nitrostyrenes. In particular, catalyst 14e prepared from L-proline and (1S,2R)-cis-1amino-2-indanol exhibits the highest catalytic performance working in polar aprotic solvents such as NMP. High syn-diastereoselectivities (up to 94% de) and good enantioselectivities (up to 80% ee) were obtained at rt. (c) 2006 Elsevier Ltd. All rights reserved.