Acridino[2,1,9,8‐ <i>klmna</i> ]acridine Bisimides: An Electron‐Deficient π‐System for Robust Radical Anions and n‐Type Organic Semiconductors
Keita Tajima, Kyohei Matsuo, Hiroko Yamada, Shu Seki, Norihito Fukui, Hiroshi Shinokubo
Abstract
Abstract We report the synthesis and properties of acridino[2,1,9,8‐ klmna ]acridine bisimide (AABI), a nitrogen‐doped anthanthrene with two imide functionalities. AABI exhibits excellent electron affinity as evident by its low‐lying LUMO level (−4.1 eV vs. vacuum). Single‐electron reduction of one AABI derivative afforded the corresponding radical anion, which was stable under ambient conditions. Photoconductivity measurements suggest that the intrinsic electron mobility of an N ‐phenethyl AABI derivative obeys a band‐transport model. Accordingly, an electron mobility of 0.90 cm 2 V −1 s −1 was attained with the corresponding single‐crystal organic field‐effect transistor (OFET) device. The vacuum‐deposited OFET device consisting of a polycrystalline sample exhibited high electron mobility of up to 0.27 cm 2 V −1 s −1 even in air. This study demonstrates that dual incorporation of both imide substituents and imine‐type nitrogen atoms is an effective strategy to create novel electron‐deficient π‐systems.