Synthesis and Properties of a Diazopentacene Analogue

We report the synthesis, optical, and electrochemical properties, as well as the organic light-emitting diode (OLED) performance of diazopentacene 2,7,11,16-tetra-tert-butyldiphenanthro[4,5-abc:4',5'-hij]phenazine (BDPP, 1). BDPP has two absorption peaks centered at 350 nm and 460 nm with a shoulder peak at 434 nm and fluoresces bright green light with the emission peak at 481 nm when excited at 360 nm in dichloromethane solution. Interestingly, the UV absorption of BDPP is sensitive to different Lewis acids and organic acids. Calculations revealed that the theoretical band gap is 2.83 eV, which is close to experimental optical data (2.69 eV). Furthermore, OLEDs that use BDPP as the emitter were fabricated. The results indicate that BDPP derivatives might be a good candidate to enhance the efficiency of OLEDs.