Polymers, Dimers and Radical Cations from Electrochemical Oxidation of Interring-Bridged Thiophene and Thiophene–Phenylene Tetramers

The electrochemical oxidation of 2,5-thienylene- (T) and 1,4-phenylene- (P) based arylene tetramers T<INF>4</INF>, TP<INF>2</INF>T and PT<INF>2</INF>P, in which the torsion angles between couples of adjacent rings are blocked by a chemical bridge, has been performed in acetonitrile. The products have been characterised by cyclic voltammetry, MALDI mass spectrometry, FT-IR, UV-vis and ESR spectroscopies, and in-situ conductivity and identified as radical cations, dimers or polymers depending on the T–P sequence in the monomer.