Journal of Molecular Catalysis A-Chemical, Vol.397, 158-165, 2015
A novel magnetic hybrid nanomaterial as a highly efficient and selective catalyst for alcohol oxidation based on new Schiff base complexes of transition metal ions
In this study, novel heterogeneous catalysts of Schiff base complexes of transition metal ions supported on silica coated magnetic metallic cobalt nanoparticles were successfully synthesized. Firstly, silica coated cobalt nanoparticles were synthesized through a one-pot reaction. Secondly, Schiff base complexes of different transition metal ions were immobilized on a magnetic support. The catalytic activity of catalysts was studied in oxidation of various aromatic alcohols with environmentally friendly oxidant under different solvents and solvent free conditions. Also, the effects of parameters such as solvent, amount of oxidant and catalysts, reaction temperature and utilization efficiency of hydrogen peroxide were investigated. The synthesized catalysts acted selectively and converted the alcohols to corresponding aldehydes with high yield. The synthesized catalysts were fully characterized by a verity of techniques such as X-ray diffraction (XRD), EDAX analysis, scanning electron microscopy and FT-IR analysis. Also, the magnetic properties of these catalysts were investigated by AGFM. The catalysts could be reused several times without significant loss in their activities. (C) 2014 Elsevier B.V. All rights reserved.