Self-Supported Noyori-Type Catalysts Using Achiral Bridged-BIPHEPs

Significance

Achiral bridged-BIPHEPs 1 reacted with [(C₆H₆)RuCl₂]₂ in DMF followed by treatment with bridged-DPEN 2 to give the self-supported catalysts 3 in almost quantitative yield (eq. 1). Aromatic ketones 4a-f were hydrogenated in the presence of self-supported catalyst 3b to give the corresponding alcohols 5a-f quantitatively with 71.9-86.9% ee (eq. 2). Catalyst 3b can be reused four times without significant loss of catalytic activity and enantioselectivity.