Minimizing base stoichiometry in Pd(0)/g-C3N4O catalyzed Suzuki–Miyaura cross-coupling reaction

Abstract

A graphitic carbon nitride oxide (g-C₃N₄O) sheet decorated with biogenically synthesized Pd nanoparticles (NPs) is designed for an efficient heterogeneous Suzuki–Miyaura cross-coupling reaction. This graphitic oxide-based material, Pd(0)/g-C₃N₄O, is directed to not only function as a catalyst but also serve as a base, to substantially minimize the requirement of an exogenous base. The g-C₃N₄O sheet is derived from guanidine hydrochloride and it plays a pivotal role in the homogeneous dispersion of Pd NPs. This bio-based catalyst exhibits a decent TOF/TON and provides excellent yields of functionalized biaryls under a sub-stoichiometric amount of exogenous base. The nitrogen-rich Lewis basic sites and the oxygen groups on the graphitic oxide surface play an important role in the activation of the boronic acid counterpart. Further, this nanocatalyst can be easily recovered from the reaction medium and reused up to five cycles without a significant loss of its catalytic activity.