Supported of Molybdenum Complex on Graphene Oxide and its Activity in the Oxidation of Sulfides

The oxidation of sulfides to sulfoxides is recognized as the best method for synthesizing these compounds. The catalytic sulfoxidation reaction has been extensively studied due to the usefulness of sulfoxides in organic synthesis. To date, a wide variety of catalysts, including metal complexes, Lewis acids, and organocatalysts, have been reported for this purpose. However, the primary challenge in this field is the recycling and recovery of the catalyst. Since catalysts are often expensive or toxic, separating them from the reaction mixture can be a time-consuming and labor-intensive process. This means increased production costs and reduced process sustainability. Therefore, the development of recyclable catalysts with high activity is considered an important goal in sulfoxidation catalysis research. In this research, a Schiff base ligand and GO were synthesized. Subsequently, GO was functionalized with ۳-chlorotrimethoxysilane (۹۸% purity). The chlorinated GO was then reacted with the synthesized Schiff base ligand under reflux to yield a ligand-anchored GO. Finally, this intermediate was reacted with a Mo (VI) source under reflux to produce the [Mo (Schiff base) O₂@GO] catalyst. The synthesized catalyst was characterized using FT-IR, XRD, EDAX, and FE-SEM. The optimal conditions for sulfide oxidation were determined: ۵ mg catalyst loading, hydrogen peroxide oxidant (۶۸ mg), ۷۰ °C, and ethanol solvent. The catalytic activity was examined with various sulfides, including methyl phenyl sulfide, dibutyl sulfide, diphenyl sulfide, benzyl phenyl sulfide, and ۲,۲'-dipyridyl disulfide. Methyl phenyl sulfide was found to be the most reactive substrate. The catalyst maintained ۹۸% conversion in the reaction after five reuses, indicating its excellent reusability.

کلیدواژه ها:

Heterogeneous catalyst ، Molybdenum complex ، Graphene oxide ، Sulfide oxidation