Synthesis and application of bulky phosphoramidites: highly effective monophosphorus ligands for asymmetric hydrosilylation of styrenes

A series of bulky monodentate phosphoramidite ligands were synthesized from chiral 3,3'-diaryl substituted BINOL derivatives and achiral or dendritic amines in good yields. Asymmetric hydrosilylation of styrenes with trichlorosilane in the presence of palladium complexes of these bulky ligands gave chiral silanes in high yields with excellent activity and productivity. Oxidation of these chiral silanes with hydrogen peroxide gave the corresponding chiral secondary alcohols in up to 96% ee.