Asymmetric aza-Henry reaction with α-substituted nitroacetates catalyzed by a bifunctional thiourea-guanidine catalyst

The asymmetric aza-Henry reaction of a-substituted nitroacetates and N-Boc imines was achieved with a new-type thiourea-guanidine bifunctional organocatalyst. The novel transformations exhibited high diastereoselectivities, and the adducts bearing adjacent quaternary and tertiary chiral centers were generally obtained in moderate to good enantioselectivities (up to 88% ee). (C) 2011 Wei Huang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.