Compound Derived from Anthracene and Pyrazol for a Light-Emitting Diode

A new compound, 5-(9-anthryl)-1,3-diphenyl-1H-pyrazol (ADPP), with an anthryl moiety as an emissive group and a diphenylpyrazoline moiety as a charge transporting group is designed and synthesized. The absorption, photoluminescence, electroluminescence, and electrochemistry are measured. Absorption of ADPP is similar to that of anthracene in the vibonic structure but shows slight red shifts because anthryl moiety twists strongly with respect to pyrazol moiety although delocalization still exists between the two moieties. Light emitting devices fabricated with ADPP show a bright blue emission at 470 nm. The turn-on voltage is 12 V and the light emission follows the current closely, indicating an efficient charge injection and transport for both electrons and holes.