Nickel and Oxo-Vanadium Complexes of Adenine on Modified Mesoporous MCM-41 as Chemoselective, Efficient, and Reusable Catalysts in the Oxidation of Sulfides and Oxidative Coupling of Thiols

A highly efficient superior catalyst of Ni (II) and VO (IV) metal complexes supported on MCM-41 has been synthesized and developed for chemoselective oxidation of sulfides to sulfoxides and oxidative coupling of thiols to their corresponding disulfides using H2O2 as a green and efficient procedure. All sulfoxides and disulfides were obtained in short reaction times with excellent yields. The over-oxidation of sulfides or thiols was not observed and all products were synthesized in high purity. These catalysts could be recovered and reused several times without any significant loss in their catalytic activity. Compared to the old catalysts in the literature, these catalysts showed better activity and selectivity for the synthesis of sulfoxide and disulfide derivatives, which shows the novelty of this work.