Cocatalytic effect of cobalt acetate on aerobic cyclohexene oxidation catalyzed by manganese porphyrin

The cocatalytic effect of cobalt acetate on the manganese porphyrin-catalyzed oxidation of cyclohexene by molecular oxygen was investigated. The conversion of cyclohexene and the selectivity toward epoxide were significantly improved, whereas the formation of 2-cyclohexen-ol was restricted in the presence of the cocatalyst. A cocatalytic mechanism involving cobalt oxide ([Co–O2]+) as the active species for enhancing cyclohexene activity and selectivity toward epoxide was proposed.

Graphical abstractHighly efficient co-catalytic effect of cobalt acetate on the manganese porphyrin catalyzed cyclohexene aerobic oxidation has been achieved.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Cocatalytic effect of Co(OAc)2 on MnTPPCl-catalyzed oxidation was observed. ► Conversion rising from 28% to 72% with Co(OAc)2 as cocatalyst was achieved. ► The valence of cobalt ion was kept unchanged during the reaction process.