Oxidative properties of [1,2-b]selenophenes and 4H-selenochromenes and their interaction with hydrogen sulfide

Electrochemical behavior of [1,2-b]selenophenes and 4H-selenochromenes in organic media and their interaction with hydrogen sulfide have been studied. In aprotic solvents (CH₂Cl₂ and CH₃CN), the organoselenium compounds are oxidized at anode to give cation-radicals. In the presence of hydrogen sulfide, at its oxidation potential (1.60 V) [1,2-b]selenophenes and 4H-selenochromenes undergo recyclization into corresponding thiophenes and thiochromenes. The recyclization yielding sulfur analogs have been studied in the presence of organic electromediators, including the transition metal complex with redox-active ligands, as well.