Cyclic voltammetry studies of n-type polymers with non-alternant fluoranthene units

Poly(p-fluoranthenevinylenes) and their dithiocarbamate precursors have been deposited on indium–tin oxide electrodes and electrochemical properties of the obtained films have been investigated by means of cyclic voltammetry studies in acetonitrile solutions containing 0.1 M (n-C4H9)4NBF4 as supporting electrolyte. It has been found that all investigated polymers display well pronounced n-doping processes. Electrochemical reduction of the dithiocarbamate precursors seems to be associated with C–S bond cleavage with elimination of –SC(S)N(C2H5)2 group. In view of UV–vis spectroscopic data the obtained products, tentatively identified as polymers containing fluoranthene units connected by –CH2–CH2– bridges, are somewhat less conjugated than the corresponding poly(p-fluoranthenevinylenes). Reversible electrochemical reduction of poly(p-fluoranthenethanes) occurs at potentials only somewhat (ca. 0.1 V) more negative as found for their poly(p-fluoranthenevinylenes) analogues suggesting relatively weak coupling between fluoranthene kernels in both kinds of investigated polymers.