Asymmetric Addition of Diethylzinc to Diphenylphosphinoyl‐Imines Catalyzed by Copper( II ) Trifluoromethanesulfonate‐Chiral (2′‐Ethylamino‐[1,1′]binaphthalenyl‐2‐yl)‐thiophosphoramidic Acid O,O′‐Diaryl Ester Ligands

The chiral binaphthylthiophosphoramide L1 prepared from the reaction of O,O‐diphenyl chlorothiophosphate with (R)‐(+)‐N‐ethyl‐1,1′‐binaphthyl‐2,2′‐diamine was used as a catalytic chiral ligand in the copper(II) trifluoromethanesulfonate‐promoted asymmetric addition of diethylzinc to diphenylphosphinoyl‐imines to give the corresponding adducts in 90–98 % ee and good yields under mild conditions.