Benzodipyrrole-2,6-dione-3,7-diylidenedimalononitrile Derivatives for Air-Stable <i>n</i>‑Type Organic Field-Effect Transistors: Critical Role of <i>N</i>‑Alkyl Substituent on Device Performance

Benzodipyrrole-2,6-dione-3,7-diylidenedimalononitriles (BDPMs) were synthesized as active materials for the use in air-stable n‑type organic field-effect transistors (OFETs), whose optical and electrochemical properties were examined. BDPM-based small molecules exhibit deep lowest unoccupied molecular orbital levels, which are required in air-stable n‑type OFETs. An OFET device that was based on BDPM-But and fabricated by vapor deposition provided a maximum electron mobility of 0.131 cm2 V–1 s–1 under ambient conditions.