Biscinchona alkaloid catalysed Henry reaction of isatins: Enantioselective synthesis of 3-hydroxy-3-(nitromethyl)indolin-2-ones

The direct catalytic enantioselective Henry (nitroaldol) reaction of isatins with nitromethane has been developed in the presence of a biscinchona alkaloid as a chiral organocatalyst. The resulting Henry adducts bearing C3-quaternary stereocentres were obtained in high yields (up to 94%) with high enantioselectivities (up to 97% ee). (C) 2011 Elsevier Ltd. All rights reserved.