Green and High-Performance Magnetic Catalysts for the Toxicity-Catalytic Reduction of Nitroarene

The reduction of the nitro group's toxicity to amine is one of the most popular reactions for the synthesis of amines (which are of great importance in various industrial, pharmaceutical, and less toxic fields). Heterogeneous catalytic systems based on metal nanoparticles are considered some of the most promising routes to implement the reduction of nitro group toxicity under sustainable conditions. In this context, for the first time, we report the preparation of novel magnetic catalysts with uniform surface areas and different particle sizes based on silver and copper nanoparticles supported on Fe₃O₄-Glycine magnetic nanocomposites Fe₃O₄-Gly-Ag and Fe₃O₄-Gly-Cu, respectively. These heterogeneous catalysts were characterized by several techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, energy-dispersive X-ray (EDX), and scanning electron microscopy (SEM). These catalysts have demonstrated excellent catalytic activity in the toxic reduction of nitroarenes to their aminoarene counterparts in the presence of NaBH₄ at room temperature in aqueous media, and they are magnetically separable using an external magnet without the need for traditional methods such as centrifugation and/or filtration. Furthermore, they are recyclable for up to five cycles without a significant loss of catalytic activity or selectivity.