Non-redox metal ion promoted oxygen transfer by a non-heme manganese catalyst

Abstract

This work demonstrates that non-redox metal ions as Lewis acids can sharply improve the oxygen transfer efficiency of a manganese(II) catalyst having a non-heme ligand. In the absence of Lewis acid, oxidation of a manganese(II) complex will generate the known di-μ-oxo-bridged dinuclear Mn₂(III,IV) core which is very sluggish for olefin epoxidation. Adding non-redox metal ions causes the dissociation of the dinuclear core, leading to sharp improvement in its oxygen transfer efficiency.