Divergent Synthesis of Benzo[d]thiazoles by PIFA-Mediated Cyclization of β-Oxo Thioamides

Efficient and divergent synthesis of benzo[d]thiazoles is developed from readily available beta-oxo thioamides mediated by hypervalent iodine reagent phenyliodine bis(trifluoroaceate) (PIFA) based on reaction conditions selection, which involves the formation of a radical cation and its subsequent intramolecular cyclization process.