Blue-Light-Emitting Bis(diarylamino)stilbene Derivatives: Synthesis, Photophysical Properties, and Highly Efficient OLEDs

New electroluminescent materials, 4,4'-bis(2-naphthyl-4-tert-butylphenylamino)-stilbene (1), 4,4'-bis(4-tert-butylphenyl-3,5-di-tert-butylphenylamino) stilbene (2), and 4,4'-bis(di-4-tert-butylphenylamino) stilbene (3) were synthesized and characterized. To evaluate the electroluminescent properties of these compounds, multilayered OLED devices 1-3 were designed. By employing blue dopant 1 into a multilayer device, it was possible to achieve a maximum luminance of 8861 cd m(-2) at 12.0 V, a luminous efficiency of 6.82 cd A(-1) at 20 mA cm(-2), a power efficiency of 2.72 lm W-1 at 20 mA cm(-2), and CIEx,y coordinates of (x = 0.158, y = 0.187) at 10.0 V. These results demonstrated the superiority of these bis(diarylamino)-stilbene derivatives in organic light-emitting devices.