pi-Extended nine-ring-fused linear thienoacenes 1a-c with internal thieno[3,2-b;4,5-b']dithiophene substructures were synthesized. Their optical and electrochemical properties were investigated. Thin-film transistor characteristics showed all compounds displayed high device reproducibility and nearly no dependence on substrate temperatures. The highest performance was observed for 1c-based devices with mobility up to 1.0 cm(2)/Vs and current on/off ratio of 10(7), whereas the maximum mobility was 0.5 cm(2)/Vs for 1b and 0.011 cm(2)/Vs for 1a.
