Highly enantioselective michael additions of α-cyanoacetate with chalcones catalyzed by bifunctional cinchona-derived thiourea organocatalyst

Abstract The conjugate addition of ethyl α-cyanoacetate with chalcones has been developed. In the presence of cinchona alkaloid-derived thiourea organocatalyst 1i (10 mol %), ethyl α-cyanoacetate could react with various chalcones to afford Michael adducts with high yields (80–92%) and enantioselectivities (83–95% ee).