Iodine catalyzed cross-dehydrogenative C-S coupling by C(sp2)-H bond activation: direct access to aryl sulfides from aryl thiols

A novel, efficient and unprecedented green protocol for the formation of C-S bonds has been developed under metal-free conditions. This protocol involves the synthesis of aryl sulfides through the cross-dehydrogenative coupling of readily available aryl thiols with electron-rich species under solvent-free conditions and the corresponding aryl sulfides are obtained in high to quantitative yields. A catalytic amount of inexpensive and non-toxic iodine drives the reaction and no exclusion of air and expensive ligands is required.