I2/DMSO-Promoted Synthesis of Diaryl Sulfide- and Selenide-Embedded Arylhydrazones

Functionalization and derivatization of arylhydrazones are important in pharmaceutical, medicinal, material, and coordination chemistry. In this regard, a facile I₂/DMSO-promoted cross-dehydrogenative coupling (CDC) for direct sulfenylation and selenylation of arylhydrazones has been accomplished utilizing arylthiols/arylselenols at 80 °C. This method provides a metal-free benign route for the synthesis of a variety of arylhydrazones embedded with diverse diaryl sulfide and selenide moieties in good to excellent yield. In this reaction, molecular I₂ acts as a catalyst, and DMSO is utilized as a mild oxidant as well as solvent to produce several sulfenyl and selenyl arylhydrazones through a CDC-mediated catalytic cycle.