Efficient Chiral Amidophosphine Ligand for Copper-catalyzed Asymmetric Addition of Diethylzinc to N-Sulfonylimines

Structure study of a chiral amidophosphine ligand for copper-catalyzed asymmetric addition reaction of diethylzinc with the N-tosylimine reached to the new chiral phosphine bearing the bulky substituent on the pyrrolidine ring, which significantly improved catalytic performance to give the adduct in 96% yield and 93% ee after 3 h.