Chiral P,O-ligands derived from N,O-phenylene prolinols for palladium-catalyzed asymmetric allylic alkylation

CuI-catalyzed N,O-arylation of (S)-prolinols and 1-bromo-2-iodobenzene afforded cyclic N,O-(1,2-phenylene)prolinols, and subsequent ortho-lithiation and phosphination provided a new type of chiral P,O-ligands. Their palladium-complex-catalyzed asymmetric allylic alkylation of dimethyl malonate with 1,3-diphenyl 2-propenyl acetate gave high yields and good enantioselectivities.