Synthesis of chiral acetoxy lactones via the Baeyer–Villiger oxidation of cyclic aromatic acetoxy ketones

The α-acetoxylation of indanones and tetralones by using Mn(OAc)3 followed by the enzyme catalyzed kinetic resolution of acetoxy ketones furnished both of the enantiomers of α-acetoxy ketones in good chemical and optical yields. The Baeyer–Villiger oxidation of α-acetoxy ketones with m-CPBA, CF3SO3H, and CH2Cl2, at rt gives the corresponding lactones without racemization. The acetoxy ketone moiety migrates selectively in order to form lactones. The mild hydrolysis of lactones affords phenolic α-hydroxycarboxylic acid derivatives.