Chiral 1,2-Diphosphine Ligands. Synthesis and Application to Rhodium-Catalyzed Asymmetric Hydrogenations

Article abstract of DOI:10.1021/jo00342a019

New chiral 1,2-diphosphine ligands, (R)-1,2-bis(diphenylphosphino)-3-(benzyloxy)propane and (R)-1,2-bis(diphenylphosphino)-3-tert-butoxypropane, have been prepared from D-mannitol.The rhodium(I) cationic complexes of these ligands are efficient asymmetric homogeneous hydrogenation catalysts for dehydro amino acids, giving (S)-amino acids in high optical yield (80-90percent).