Synergistic Catalysis of Se and Cu for the Activation of α-H of Methyl Ketones with Molecular Oxygen/Alcohol to Produce α-Keto Acetals^†

Selenium and copper synergistically catalyzed the oxidation/alkoxylation of methyl ketones to synthesize α-keto acetals directly. Using O₂ as oxidant and alcohol as solvent and alkoxylation reagent, the reaction is practical from industrial viewpoint. Mechanistic studies revealed that copper promoted the oxidation of organoselenium intermediates with O₂ to allow the key rearrangement and selenoxide syn-elimination regenerating the catalytically active organoselenium species.