Enantioselective catalysis of epoxidation by metalloporphyrins: application to enantioselective synthesis

A wide variety of asymmetric metalloporphyrins have been prepared in an effort to develop catalysts for the enantioselective epoxidation of unfunctionalized olefins. As yet, no porphyrin-based catalyst has shown sufficient selectivity to be applied in general synthesis. Therefore, this review focuses specifically on the developments that are leading toward synthetically useful metalloporphyrin epoxidation catalyst, specifically addressing catalyst stability and activity, ease of catalyst preparation, and the potential for improvement of specific catalyst designs.