Nano Pd–Fe3O4@Alg beads: as an efficient and magnetically separable catalyst for Suzuki, Heck and Buchwald–Hartwig coupling reactions†
Abstract
Catalytic processes are the backbone of many chemical industries. In a comparative study of various heterogeneous catalytic systems, we report efficient and magnetically separable nano Pd–Fe3O4@Alg beads as catalysts for Suzuki, Heck and Buchwald–Hartwig coupling reactions. This catalyst was characterized by SEM, TEM, HRTEM, XRD, EDAX, FT-IR, VSM, DSC-TGA, BET, and UV-Visible spectroscopy. This heterogeneous catalyst showed high catalytic activity and stability for C–C and C–N bond forming coupling reactions with excellent product yield under ligand free conditions. The beads of nano Pd–Fe3O4@Alg can be separated from the reaction mixture by an external magnet and reused for several successive cycles with no appreciable loss in the catalytic activity. The Suzuki and Heck coupling reactions in aqueous medium are greener routes, which is an added advantage of this protocol.