Thiophene/cyclopentadiene regular copolymers from electrochemical oxidation of dithienylcyclopentadienes

Anodic coupling to polymer of some dithienyleyclopentadienes has been performed in acetonitrile. The polymers have been characterized by cyclic voltammetry, UV vis, MALDI mass and FT-IR spectroscopies, and in situ conductivity. Nonsubstituted dithienylcyclopentadiene undergoes coupling both at the thiophene ?-position and at the internal cyclopentadiene sites with the production of an insoluble polymer corresponding to a tetrameric formulation. Protection of the cyclopentadiene 5 position with alkyl chains has allowed the production of regularly ?-coupled polymers. The optical gap of poly(dithienylcyclopentadiene) has been evaluated as 2.2 eV, i.e., close to that of polythiophene (2.3 eV).