Effects of ultrasound and microwave irradiation on the green oxidation of alkylarenes by KMNO4/CUSO4-5H2O

Abstract

Potassium permanganate oxidized some alkylarenes such as ethylbenzene (1), propylbenzene (2), diphenylmethane (3), cumene (4), 1-bromo-2-phenylethane (5), indane (6), tetraline (7), and fluorene (8) at the benzylic position to form the corresponding aromatic ketones under solventless reaction conditions. Under the assisstance of ultrasound and microwave irradiation, the reaction times were reduced remarkably without a decrease of the yield. Reaction factors including the molar ratio of substrates, KMnO₄, CuSO₄ 5H₂O, reaction time, microwave power were optimized to achieve the highest conversion yields and product selectivities.