Green synthesis of carbon quantum dots from vanillin for modification of magnetite nanoparticles and formation of palladium nanoparticles: Efficient catalyst for Suzuki reaction

Abstract

In this report we prepared carbon quantum dots (CQD) from vanillin as an ecofriendly and naturally abundant compound for modification of magnetic nanoparticles (CQD@Fe3O4 NPs). This new magnetic solid has been used for complete reduction of PdCl2 with formation of stabilized palladium nanoparticles (Pd@CQD@Fe3O4 NPs) and characterized by SEM, TEM, EDX, solid UV, VSM, XPS, XRD, and N2 adsorption–desorption analyses. These magnetic supported Pd NPs have been used as an efficient catalyst for the Suzuki-Miyaura cross-coupling reactions of aryl bromides at room temperature in aqueous ethanol and of aryl chlorides at 120 °C in PEG200 under low catalyst loading in air. The heterogeneous catalyst can be easily recovered by an external magnet and reused for eight consecutive runs.