Synthesis of Selenocyanated Indoles via PhICl₂-Induced Electrophilic Intramolecular Cyclization of 2-Alkynylanilines or 2-Alkenylanilines

The 3-selenocyanato-substituted indoles were readily synthesized via (dichloroiodo)benzene (PhICl2)-induced reaction of 2-alkynylanilines or 2-alkenylanilines with KSeCN in MeCN under metal-free conditions. The reaction sequence was postulated to encompass the formation of a reactive selenocyanogen chloride species, generated in situ from the reaction of PhICl2 and KseCN, followed by electrophilic addition and intramolecular cyclization steps.