Green oxidation of 2-imidazolines with tert-butyl hydroperoxide catalyzed by supported manganese(III) porphyrin in water

Abstract

Green oxidation of 2-substituted imidazolines with tert-butyl hydroperoxide catalyzed by tetraphenylporphyrinatomanganese(III) chloride, [Mn(TPP)Cl], supported on polystyrene and silica bound imidazole is reported. A variety of 2-imidazolines were efficiently converted to their corresponding imidazoles by these catalytic systems in H₂O. Ultrasonic (US) irradiation enhanced the catalytic activity of these catalysts and higher product yields were observed at shorter reaction times. These catalysts were re-used several times without significant loss of their catalytic activities. The effect of reaction parameters such as catalyst amount, reaction temperature, and the effect of US irradiation on the catalytic activity was also investigated.

Keywords:

• Manganese(III) porphyrin
• TBHP
• Imidazolines
• Oxidation
• Supported catalyst
• Ultrasonic irradiation

Acknowledgments

The partial support of this work by Payame Noor, University of Ardakan, is acknowledged.