Conveniently Synthesized Butterfly-Shaped Bitriphenylenes and their Application in Solution-Processed Organic Field-Effect Transistor Devices

Various π-extended new bitriphenylene derivatives (both conformationally-free and conformation-locked) have been successfully synthesized by a facile Scholl oxidative cyclodehydrogenation method in good to excellent yields. Their optical properties in solution and film states reveal possibility for self-ordering. The molecular packing in solid-state demonstrates favorable π–π stacking as well as weak intermolecular interactions leading to face-to-face or slipped-stack arrangements. Besides, these butterfly-shaped large bitriphenylenes display near-UV absorption, excellent photochemical, thermal, and electrochemical stabilities. The all-organic anneal-free transparent FETs fabricated from solution-processable bitriphenylenes showcase significant improvement (ca. 4 orders of magnitude higher) in charge transporting abilities (µh: from ca. 10–7 to 10–3 cm2/(Vs)) when compared to model triphenylene. The fabricated FETs unveil excellent air stability (> 1 year under atmospheric conditions) highlighting the utility of these novel link-locked triphenylene skeletons in organic electronics.