Synthesis of [1]benzothiopheno[2,3-b][1]benzothiophene derivatives through iodine-mediated sulfuration reaction of 1,1-diarylethylenes

[Display omitted] •BTBTs are generated at once by the Quadruple CS bond formation.•The addition of molecular iodine accelerates the formation of BTBTs.•3-Arylbenzo[b]thiophenes are also prepared by changing reaction conditions. Acceleration of the reaction for the synthesis of [1]benzothiopheno[2,3-b][1]benzothiophenes (BTBTs) from 1,1-diarylethylenes was accomplished by the addition of molecular iodine. Postulated intermediates 3-arylbenzo[b]thiophenes were also selectively prepared by simply changing the amount of iodine and the reaction time.