Direct Electrooxidative Selenylamination of Alkynes: Access to 3-Selenylindoles

A novel metal- and oxidant-free electrooxidative selenylamination of o-aminophenacetylenes with diselenides for achieving 3-selenylindoles has been developed with moderate to excellent yield. The reaction proceeded smoothly with a broad substrate scope and highly functional group tolerance. The synthetic practicality of this innovative approach was demonstrated by its easy scalability. Moreover, mechanistic studies revealed that an in-situ generated selenium cation might be the key intermediate for the electrochemical selenocyclization process.