Nickel Schiff base complex anchored on Fe₃O₄@MCM-41 as a novel and reusable magnetic nanocatalyst and its application in the oxidation of sulfides and oxidative coupling of thiols using H₂O₂

A novel and reusable nanocatalyst was synthesized by anchoring a nickel Schiff base complex onto Fe₃O₄@MCM-41 (Fe₃O₄@MCM-41@Ni-P2C) and characterization was accomplished with Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), vibrating sample magnetometry (VSM), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic absorption spectroscopy (AAS) techniques. This catalytic system was efficiently used for oxidation of sulfides to sulfoxides and oxidative coupling of thiols to corresponding disulfides using H₂O₂ as green oxidant at room temperature. These reactions were carried out in a green solvent (ethanol) and/or under solvent-free conditions with short reaction time, complete selectivity and very high conversion under mild reaction conditions. More importantly, separation and recycling of this magnetic catalyst can be easily done through a simple and low cost magnetic separation process.