DABCO tribromide immobilized on magnetic nanoparticle as a recyclable catalyst for the chemoselective oxidation of sulfide using H2O2 under metal- and solvent-free conditions

Magnetic nanoparticle-supported 1,4-diazabicyclo[2.2.2] octane tribromide (MNPs-DABCO tribromide) as a bromine source was readily prepared and characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM) techniques. The catalytic activity of MNPs-DABCO tribromide was investigated in the chemoselective oxidation of sulfides to sulfoxides using 30% H2O2 as an oxidant at room temperature under solvent-free conditions. The heterogeneous catalyst could be recovered easily and reused 15 times without significant loss of its catalytic activity. (C) 2013 Elsevier B.V. All rights reserved.