Non-Metallic Ketone Compounds Catalyzed Selective Epoxidation of Styrene with Dry Air

Two non-metallic ketone catalysts resulted from fructose were first applied in the epoxidation of styrene with dry air to achieve considerably encouraging results, in which no any transition metal ion/oxide was involved. Ketone 1 was highly active, with the styrene conversion of 78.1 mol% and the epoxide selectivity of 92.0% at 363 K in 5 h. The poorer activity of ketone 2 was possibly associated with stronger steric hindrance of intermediate coordinative state. The occurrence of styrene epoxidation with dry air over the ketone could involve the coordination among solvent DMF, oxygen and ketone to form the peroxy ketone intermediate.