The catalytic activity of two magnetic catalysts Fe3O4@SiO2@DOPisatin‐M(II) (M = Ni, Cu) was investigated in the environmentally green H2O2 oxidant‐ based oxidation of sulfides to sulfoxides and oxidative coupling of thiols to disulfides. By using these catalysts, various substrates were successfully converted into their corresponding product. These catalysts could also be reused multiple time without significant loss of activity. The physical and chemical properties of the catalysts were determined using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), energy dispersive X‐ray spectroscopy (EDX) and atomic absorption spectroscopy (AAS).
