Chiral Bronsted Acid-Catalyzed Enantioselective α-Hydroxylation of β-Dicarbonyl Compounds

A novel, facile, and highly enantioselective Bronsted acid-catalyzed alpha-hydroxylation of beta-dicarbonyl compounds with up to 99:1 er using nitroso compounds as the oxygen source has been developed. The results disclosed herein considerably extend the substrate scope for the alpha-aminoxylation, allowing expeditious, straightforward, and efficient access to valuable alpha-hydroxy-beta-dicarbonyl compounds with the highest levels of enantiocontrol.