Chiral binaphthylthiophosphoramide-cu(I)-catalyzed asymmetric addition of diethylzinc to N-sulfonylimines.

In the presence of a catalytic amount of chiral binaphthylthiophosphoramide L2 (6 mol %) and Cu(I) (3 mol %), the asymmetric addition of diethylzinc to N-sulfonylimines could be achieved in good yields with moderate to high ee (63-93% ee) at 0 degrees C in toluene. A novel chiral binaphthylthiophosphoramide ligand system for this asymmetric addition reaction has been explored.