Aerobic Oxidation of Olefins to Epoxides Using a Copper(II)-Aldehyde System

Abstract

Epoxidation of olefins was successfully achieved using molecular oxygen in the presence of an aldehyde and a catalytic amount of CuCl₂ at room temperature. Hexanal was found to be a particularly good reducing agent for the CuCl₂-catalyzed epoxidation. A good correlation was observed between the reactivity and the calculated ionization potential for some of the aldehydes tested. The present system was applied to epoxidation of a range of olefins in high to excellent yields.