Synthesis of Optically Pure Bisphosphine Oxides and Related Compounds

Abstract

Abstract Optically pure bisphosphine oxides were conveniently synthesized by Kolbe electrolytic coupling reaction of carboxylic acids possessing a chiral phosphinoyl group in 60—65% isolated yield. This synthetic approach provides a variety of accesses to P-chiral bisphosphine ligands. Their absolute configurations were intercorrelated with that of the previous reported BisP*-borane. Asymmetric hydrogenation of α-(acylamino)acrylic acids by a rhodium complex with BisP* (R = t-octyl or 1,1,3,3-tetramethylbutyl) affords N-acylamino acids in 94—96% ee.