Rhodium-Catalyzed Reductive Aldol Reaction of Vinyl Ketones

Significance

The authors report the first enantio­selective reductive aldol coupling of vinyl ketones, which were achieved through the design of a new class of TADDOL-like phosphonite ligands (AP I - AP IV). Hydrogenation of commercially available methyl vinyl ketone or ethyl vinyl ketone in the presence of aldehydes using cationic rhodium catalysts modified by chiral phosphonite ligands produces aldol adducts with excellent control of relative and absolute stereochemistry.