摘要:
The conjugate addition of ethyl alpha-cyanoacetate with chalcones has been developed. In the presence of cinchona alkaloid-derived thiourea organocatalyst 1i (10 mol %), ethyl alpha-cyanoacetate could react with various chalcones to afford Michael adducts with high yields (80-92%) and enantioselectivities (83-95% ee). (c) 2007 Elsevier Ltd. All rights reserved.