Improved Synthesis and Electrophilic Bromination of Benzodithiophene. Charge-Transfer and Cycloaddition Reaction with Tetracyanoethylene

Article abstract of DOI:10.1021/jo00180a013

Benzo<1,2-c:3,4-c'>dithiophene (6) is prepared in two steps and 47percent overall yield from its tetrahydro precursor 7.Bromination of 6 ( NBS, AcOH) occurs in the thiophene moities; preparation of the 1-Br, 3-Br, 1,3-Br2, 1,3,6-Br3, 1,3,6,8-Br4, and 1,3,