Synthesis of original phosphine-sulfoxide ligands for asymmetric allylic alkylation

New phosphine-sulfide and phosphine-sulfoxide ligands were synthesized and tested in allylic alkylation. Their coordination mode with Palladium have been studied by analysis of the corresponding X-ray crystallographic structures. The most efficient ligands were prepared in enantiomerically pure form and were applied to the Pd-catalyzed asymmetric allylic alkylation providing enantioselectivities up to 74%.