Enhancement of the catalytic activity of Pd nanoparticles in Suzuki coupling by partial functionalization of the reduced graphene oxide support with p-phenylenediamine and benzidine

This paper reports the development of novel supports for highly active Pd nanoparticles for room temperature Suzuki cross coupling reactions. The partial functionalization of the reduced graphene oxide support by the N-containing p-phenylenediamine and benzidine molecules results in the dispersion of small Pd nanoparticles in the solid catalysts Pd/(RGO-PPD) and Pd/(RGO-BZD) which demonstrate excellent catalytic activity for Suzuki coupling under ligand-free ambient conditions with unusual catalytic activity that matches that of the best homogeneous Pd catalysts. They offer remarkable turnover frequencies (400,000 h(-1)) observed in the microwave-assisted Suzuki cross coupling reaction with easy removal from the reaction mixture, recyclability with no loss of activity, and significantly better performance than most of the reported heterogeneous Pd catalysts. The findings illustrate the exciting opportunities presented by the chemically partially functionalized reduced graphene oxide support for a variety of metallic and bimetallic catalysts for carbon-carbon bond forming reactions. (C) 2020 Elsevier Inc. All rights reserved.