Synthesis and characterization of Fe3O4@SiO2@L-Arginine@Cu as a new, recoverable and heterogeneous nanocatalyst for the selective and mild oxidation of sulfides and oxidative coupling of thiols

In this paper, we report fabrication and characterization of a stable heterogeneous nanostructure catalyst, Cu immobilized on Fe3O4@SiO2@L-Arginine, for the oxidation of sulfides and oxidative coupling of thiols. These nanoparticles were effective catalyst for selective oxidation of sulfides and oxidative coupling of thiols using 30% H2O2. The prepared catalyst has been characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction spectroscopy (XRD), N2 adsorption/desorption isotherms (BET), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and inductively coupled plasma (ICP) analysis. The suggested method offers several prominent advantages such: mild condition, use of magnetically reusable catalyst, simple work up procedure, and great selectivity. The significant features of this newly developed procedure are easy separation of the catalyst from reaction mixture using an external magnet and its reusability, operational simplicity, applicability to various substrates and high yields of products. The catalytic activity of the catalyst remains unaltered after five consecutive cycles.