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.