Synthesis of Substituted Benzo[b]thiophenes via Base-Promoted Domino Condensation–Intramolecular C–S Bond Formation

A novel synthesis of 2,3-substituted benzothiophenes is reported, involving a tandem base-mediated condensation of o-iodoarylacetonitriles/acetates/ketones with (hetero)aryldithioesters and an intramolecular C–S bond formation. The reaction affords diversely substituted benzothiophenes and heterofused thiophenes in excellent yields.