Preparation of new chiral peralkyldiphosphines as efficient ligands for catalytic asymmetric hydrogenation of α-dicarbonyl compounds

Abstract

New chiral peralkyldiphosphines (5) containing a pyroolidine ring have been prepared by a new method, which is widely applicable to transformation of known chiral diphosphines into the corresponding cyclohexyl analogues; asymmetric hydrogenation of α-dicarbonyl compounds catalysed by rhodium complexes of (5) proceeds smoothly under mild conditions (1 atm H₂; 35°C) to give moderate optical yields.