Syntheses and Properties of Nine-Ring-Fused Linear Thienoacenes.

π-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 cm²/Vs and current on/off ratio of 107, whereas the maximum mobility was 0.5 cm²/Vs for 1b and 0.011 cm²/Vs for 1a. [ABSTRACT FROM AUTHOR]