Trichloroisocyanuric Acid (TCCA): A Suitable Reagent for the Synthesis of Selanyl‐benzochalcogenophenes

A new approach for the synthesis of 3‐organoselanyl‐benzo[b]chalcogenophenes promoted by trichloroisocyanuric acid is reported. The reaction was carried out with electrophilic selenium species which were generated in situ by the reaction between trichloroisocyanuric acid and diorganyl diselenides using ethanol as solvent. The developed method uses mild reaction conditions and was efficient for the synthesis of different 3‐organoselanyl‐benzo[b]chalcogenophenes in a good to excellent yields. Analysis of 77Se NMR spectroscopy indicates that the electrophilic PhSeCl was formed in situ and a plausible reaction mechanism was proposed.