Metal-Free Sustainable Synthesis of Amides via Oxidative Amidation Using Graphene Oxide as Carbocatalyst in Aqueous Medium

We describe an efficient, clean and metal-free procedure for the synthesis of amides via oxidative amidation of aldehydes with anilines using graphene oxide (GO) as a recyclable catalyst and KBrO3 as a mild oxidant in aqueous medium under microwave irradiation. GO nanosheets were prepared and characterized by XRD, TEM, SEM, and FT-IR, analyses. GO showed high compatibility with KBrO3 in water and offered high TOF value (1.30 x 10(-3) mol g(-1) min(-1)). GO oxygen functionalities catalyze the oxidative amidation effectively in mild condition with high recyclability. A plausible mechanism was proposed by the isolating the intermediate.