Molecular Iodine Promoted Divergent Synthesis of Benzimidazoles, Benzothiazoles, and 2-Benzyl-3-phenyl-3,4-dihydro-2H-benzo[e][1,2,4]thiadiazines

An unprecedented formation of a new class of 2-benzyl-3-phenyl-3,4-dihydro-2H-benzo[e][1,2,4]thiadiazines has been discovered during the course of benzimidazole and benzothiazole synthesis, through the molecular iodine-mediated oxidative cyclization with a new C-N and S-N bond formation at ambient temperature.