A green methodology for thioether formation reaction and synthesis of symmetrical disulfides over new heterogeneous Cu attached to bifunctionalized mesoporous MCM-41

Abstract

Abstract Bifunctional porous nanomaterials are in high demand for heterogeneous catalysis. In this exploration, a new recyclable Cu attached bifunctionalized mesoporous MCM-41 (MCM-41-quinoline-2-4-dicarboxylic acid-Cu) has been developed through post-functionalization modification of silica MCM-41. This catalyst was demonstrated to be a novel, effective, and greener catalyst for the thioether formation reaction between aryl halides and S8, instead of thiol, and synthesis of disulfides by coupling of aromatic thiols with molecular O2 (air). This protocol is a greener way toward the thioether formation reaction and the synthesis of disulfides and shows a 100% atom economy. In this system, thioether is produced as the only product. One way that chemists evaluate a synthetic route is to focus on its atom economy, the proportion of reactant atoms that end up in the desired product. The efficiency of synthesis is quantified in terms of the percent atom economy: The catalytic system exhibits high chemo-selectivity, as shown by high yields. The catalyst can be easily separated using simple recovery and reused several times with consistent activity.