Fused Pyrazine‐ and Carbazole‐Containing Azaacenes: Synthesis and Properties. Issue 9 (23rd July 2019) - Liao, Hailiang
Abstract: A new family of azaacenes has been designed and synthesized by incorporating the electron‐withdrawing sp 2 ‐hybridized nitrogen of pyrazine and electron‐donating nitrogen of carbazole in a molecular skeleton. Two different conjugated lengths of 8‐ring aza‐nonacene and 10‐ring aza‐undecene have been achieved by an efficient condensation reaction. The unique optoelectronic properties of these molecules were investigated using both experimental and theoretical techniques. The azaacenes show visible‐region absorption and near‐infrared (NIR) fluorescence. These compounds can serve as hole‐transport semiconductors for solution‐processed organic field‐effect transistors (OFETs). Single‐crystal transistor devices of one of the aza‐nonacenes exhibit hole charge transport behavior with a hole mobility of 0.07 cm 2 /Vs and an on/off current ratio of 1.3x10 6 . Abstract : An addition to the family : A new family of azaacenes have been designed and synthesized by incorporating the electron‐withdrawing sp 2 ‐hybridized nitrogen of pyrazine and electron‐donating nitrogen of carbazole in a molecular skeleton. The azaacenes show absorption in the visible region and near‐infrared (NIR) fluorescence. Micrometer‐sized single‐crystal field effect transistor devices of one of the aza‐nonacenes exhibit hole charge transport behavior with a hole mobility of 0.07 cm 2 /Vs and an on/off current ratio of 1.3×10 6 .