Synthesis of N,N-dimethyl-2-amino-1,2-dicyclohexylethanol and its application in the enantioselective conjugate addition of diethylzinc to enones: a convenient upgrade of the chiral ligand via hydrogenation

The effectiveness of N,N-dimethyl-2-amino-1,2-diphenylethanol as a chiral l igand was significantly improved via simple hydrogenation of the phenyl rin gs. Both the catalytic activity and the enantioselectivity of the resulting new ligand in the asymmetric conjugate addition of diethylzinc to enones w ere found to be superior to the original phenyl analog. (C) 2001 Published by Elsevier Science Ltd.