No abstract

The epoxidation catalyzed by transition metals (Cr, Ni, Co, Ru, Mn) has been received widespread attention over the past decades, and the corresponding epoxides are widely used in the synthesis of pharmaceuticals, fine chemicals and pesticides. Compared to other transition metals, metal Mn catalyst has been widely used in organic synthesis due to its inexpensive, environment-friendly, chemical stability and high catalytic activity. This paper reviews the recent progress on epoxidation of olefins catalyzed by the catalysts which were formed by the reaction of different valence metal Mn(II, III, and V) and different N X O Y ligands in different oxidants/co-catalyst systems. At the same time, the Mn catalysts with different valence states are involved in the process of the epoxidation of olefins and the mechanism of how to transfer the oxygen of reactive intermediates to the olefins was discussed.