Pd–Ni bimetallic catalyst supported on dendrimer-functionalized magnetic graphene oxide for efficient catalytic Suzuki-Miyaura coupling reaction

A novel type of dendritic structure was grown on the magnetic graphene oxide nanocomposite surface through thiol-ene click reaction. The resulting nanocomposite was utilized as a support for immobilizing Pd–Ni bimetallic nanoparticles, which were employed in catalytic Suzuki-Miyaura coupling reaction. Transmission electron microscopy and X-ray diffraction analyses confirmed the small size and high dispersity of Pd–Ni nanoparticles. The catalyst efficiently promoted the Suzuki-Miyaura reaction of various aryl bromides and chlorides with arylboronic acids, with excellent yields under mild conditions. The combination of Pd and Ni nanoparticles together with dendritic structure of the catalyst ultimately resulted in the excellent catalytic activity. Not only the existence of dendrimer with high cavities provided the fast adsorption of reactants, but also the synergistic effect between two metals greatly increased the catalytic activity. More importantly, the introduction of Ni significantly increased the catalyst cost-effective. By magnetic separation of the catalyst, it could be retrieved for five times with no remarkable change of activity.