Selective Oxidation of Benzylic C–H Using Nanoscale Graphene Oxide as Highly Efficient Carbocatalyst: Direct Synthesis of Terephthalic Acid

Abstract

Nanoscale graphene oxide sheets (NGO), as activated carbocatalysts, were synthesized by a reduction size strategy and used in chemoselective oxidative conversion of benzylic C–H to the corresponding carboxylic acid. On the basis of the results of the optimization process of different parameters, 3 equiv of H 2 O 2 for each C–H group, 100 wt % of NGO in aqueous medium, acetone as a cosolvent, and a reaction temperature of 100 °C were selected as optimum parameters. In this optimum condition, xylenes and toluene over 24 h with good yield were converted to the corresponding carboxylic acid, and in the case of diphenylmethane and ethylbenzene, these substrates with excellent yield were converted to benzophenone and acetophenone.