Zirconium oxide complex-functionalized MCM-41 nanostructure: an efficient and reusable mesoporous catalyst for oxidation of sulfides and oxidative coupling of thiols using hydrogen peroxide

Zirconium oxide complex-functionalized mesoporous MCM-41 (Zr-oxide@MCM-41) as an efficient and reusable catalyst is reported for the oxidation of sulfides into sulfoxides using hydrogen peroxide (H2O2) as the oxidant, with short reaction times in good to excellent yields at room temperature under solvent-free conditions. Also, a simple and efficient method is reported for the oxidative coupling of thiols into corresponding disulfides in good to high yields using H2O2 as oxidant in the presence of Zr-oxide@ MCM-41 as recoverable catalyst in ethanol at room temperature. A series of sulfides and thiols possessing functional groups was successfully converted into corresponding products. After completion of reactions the catalyst was easily separated with simple filtration from the reaction mixture and reused for several consecutive runs without significant loss of catalytic efficiency. The mesoporous catalyst was characterized using Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller surface area measurements, X-ray diffraction, transmission and scanning electron microscopies, energy-dispersive X-ray spectroscopy and thermogravimetric analysis. Copyright (C) 2015 John Wiley & Sons, Ltd.