Iodine-mediated, chalcogen–chalcogen bond formation in water: green synthesis of carbamo(dithioperoxo)thioates, carbamo(selenothioperoxo)thioates, carbono(dithioperoxo)thioates, and carbono(selenothioperoxo)thioates

Abstract

Herein, we disclose an iodine-mediated, three-component versatile synthetic strategy for the green synthesis of a wide variety of biologically active carbamo(dithioperoxo)thioates including a couple of anti-filarial and anti-tumour agents, along with their new classes of promising analogues, such as carbamo(selenothioperoxo)thioates, carbono(dithioperoxo)thioates, and carbono(selenothioperoxo)thioates. This strategy employs only readily available and inexpensive reactants or reagents, such as iodine, diorganyl disulfides or diselenides, amines, and carbon disulfide (CS₂) or potassium xanthate to access potential classes of molecules by enabling the formation of chalcogen–chalcogen bonds (S–S and S–Se) in an aqueous environment at ambient temperature under aerobic conditions. Notably, two synthetically challenging yet promising classes of molecules, namely carbamo(selenothioperoxo)thioates and carbono(selenothioperoxo)thioates, have been successfully synthesized in a sustainable manner in water at room temperature through the formation of the challenging S–Se bond for the first time. The reaction proceeded through the in situ formation of the corresponding chalcogenyl iodides, followed by nucleophilic substitution at the chalcogen center by the in situ generated dithiocarbamates or xanthate, as the major path, to afford the desired product along with the formation of non-hazardous by-products or waste, i.e., NaI and H₂O or KI.