Graphene Oxide as a Carbocatalyst for Sustainable <i>ipso</i>-Hydroxylation of Arylboronic Acids: A Simple and Straightforward Strategy To Access Phenols

Abstract

A metal-free and straightforward protocol for the synthesis of phenols from aryl and heteroaryl boronic acids has been demonstrated using graphene oxide as a carbocatalyst. This sustainable ipso-hydroxylation takes place under mild conditions using aqueous H2O2 as an oxidant in a water medium in a short time under organocatalytic and base-free conditions. The control experiments reveal that the presence of carboxyl groups promotes ipso-hydroxylation. The developed methodology offers GO as a benign solid-acid catalyst with good sustainability which can be reused several times without significant loss in its catalytic activities; this was proven by the Fourier transform infrared and powder X-ray diffraction studies of the reused catalyst.