Reduced graphene oxide supported Ni nanoparticles: a high performance reusable heterogeneous catalyst for Kumada-Corriu cross-coupling reactions

Reduced graphene oxide (RGO) has emerged as an excellent 2D catalyst support. A high concentration of air stable Ni(0) nanoparticles (similar to 40 wt%) of average size 11 nm can be loaded on reduced graphene oxide. In this article Kumada-Corriu cross-coupling reactions have been studied extensively using RGO supported 40 wt% Ni nanoparticles (Ni/RGO-40) as a heterogeneous catalyst. The reaction conditions were optimized by performing the cross-coupling between 4-iodoanisole and phenylmagnesium chloride in the presence of a catalytic amount of Ni/RGO-40. A detailed study of the catalysis was performed by varying the haloarenes and Grignard reagents under the optimized conditions with yields of 91-72%. The products were characterized by H-1 and C-13 NMR spectroscopy. The catalyst was found to be significantly reusable. Finally the recovered Ni/RGO-40 was characterized by X-ray diffraction (XRD) and Raman spectroscopy and found to be unaffected. Considering the catalytic performance, reusability and economic reasons, Ni/RGO-40 can be of technological importance.