Highly enantioselective conjugate addition of diethylzinc to a, β-unsaturated lactones was achieved by using chiral diphosphite-copper catalysts; the structure of a chiral diphosphite-copper (I) catalyst was determined by single crystal X-ray diffraction.

Chiral aryl diphosphite ligands derived from binaphthol were found to be effective in the nickel-catalyzed hydrocyanation of a variety of olefins. Enantioselective hydrocyanations of styrene, 4-substituted styrenes and norbornene were achieved with excellent regioselectivity and moderate enantioselectivity. The hydrocyanation of vinyl acetate gave 72.9% ee. The catalytic activity and the enantioselectivity of the Ni(0)-diphosphite complexes were found to be highly dependent on the structures of the ligands.

A series of C2-symmetric aryl diphosphites based on chiral binaphthol were prepared and their copper complexes were found to be efficient catalysts for the conjugate addition of diethylzinc to cyclic enones. Good enantioselectivities (up to 89.8 and 88.7% ee, respectively) were obtained in the conjugate addition of diethylzinc to 2-cyclohexenonc and 2-cyclopcntenone.