Phase-Transfer-Catalyzed Enantioselective α-Hydroxylation of Acyclic and Cyclic Ketones with Oxygen

An efficient and enantioselective α-hydroxylation of acyclic as well as cyclic ketones using molecular oxygen has been developed. This simple catalytic procedure uses a readily available phase-transfer catalyst and produces a wide range of valuable tertiary α-hydroxy ketones in good to excellent enantiopurity.