Epoxidation of Olefinic Compounds with Combined Use of Molecular Oxygen and Propionaldehyde Diethyl Acetal Catalyzed by Cobalt(II) Complex. Efficient Method for the Preparation of Acid-sensitive Epoxides

Abstract
Synthesis of acid-sensitive epoxides such as epoxide of bishomoallyl alcohol or chromene oxide was achieved by the epoxidation of corresponding olefins with combined use of molecular oxygen and propionaldehyde diethyl acetal catalyzed by cobalt(II) complex. Various silyl enol ethers and silyl ketene acetals, acid-sensitive compounds, were also smoothly monooxygenated into the corresponding α-hydroxy carbonyl compounds.