An electrosynthetic method is developed for synthesizing selenyl-chalcogenophenes via intramolecular cyclization of (Z)-chalcogenenynes under mild conditions and without external oxidants. Density functional theory calculations and cyclic voltammetry support the experimental results and help propose plausible mechanistic pathways.

Herein, an efficient and more environmentally benign electrosynthetic approach is reported for the intramolecular chalcogeno cyclization of (Z)-chalcogenoenynes, resulting in seleno-chalcogenophene derivatives. The reaction proceeds in an undivided cell in constant current and equipped with platinum electrodes by using 5 mL of acetonitrile as a solvent, 0.2 mmol of the (Z)-chalcogenoenyne, 2 equiv. of diorganoyl diselenide and 0.2 equiv. of electrolyte, 18 overall compounds are synthesized with yields between 52% and 97%. Control experiments and density functional theory studies are also conducted to propose plausible mechanistic pathways. Furthermore, selected compounds are screened via spectrophotometric titration to assess their potential interactions with DNA, with results indicating that both groove and intercalation interactions occure depending on the structure and concentration of the seleno-chalcogenophene compound. This electrochemical procedure presents itself as a viable and cost-effective alternative for the synthesis of chalcogenophenes, as it doesn't require external oxidants, operates under mild reaction conditions, and affords its products in good to excellent yields.