Novel 1-arylbenzo [b] thiophenium salts (4) are prepared by bromine-induced intramolecular cyclization of [o-(arylthio) phenyl] ethenes (3). The substituent and solvent effects on the formation of the 1-arylbenzo [b] thiophenium salts 4 are described. The reaction with iodine monochloride provides the improved yields of 2-unsubstituted and 2-methyl-1-phenylbenzo [b] thiophenium salts 4. The single crystal structure of 1, 2, 3-triphenylbenzo [b] ...
