Three fused polycyclic aryl fragments, namely, naphthyl, methoxynaphthyl, and pyrenyl have been used to construct blue-emissive phenanthroimidazole-functionalized target molecules, i.e., 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-2-(naphthalen-1-yl)-1H-phenanthro[9,10-d]imidazole (1), 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-2-(1-methoxynaphthalen-4-yl)-1H-phenanthro[9,10-d]imidazole (2), and 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-2-(pyren-10-yl)-1H-phenanthro[9,10-d]imidazole (3). The up-conversion of triplets to singlets via a triplet–triplet annihilation (TTA) process is dominant in these compounds due to 2E_T1 > E_S1. The pyrenyl dihydrobenzodioxin phenanthroimidazole (3)-based nondoped OLED exhibits blue emission (450 nm) with CIE (0.15, 0.14), a luminance of 53 890 cd m⁻², power efficiency of 5.86 lm W⁻¹, external quantum efficiency of 5.30%, and current efficiency of 6.90 cd A⁻¹. The efficient device performance of pyrenyl dihydrobenzodioxin phenanthroimidazole is due to the TTA contribution to the electroluminescent process.

中文翻译：

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为非掺杂蓝色有机发光器件定制扭曲的二氢苯并二恶英菲并咪唑衍生物的分子设计†

三个稠合的多环芳基片段，即萘基、甲氧基萘基和芘基已被用于构建蓝色发射的菲并咪唑功能化靶分子，即1-(2,3-dihydrobenzo[ b ][1,4]dioxin-6- yl)-2-(naphthalen-1-yl)-1 H - phenanthro[9,10- d ]imidazole ( 1 ), 1-(2,3-dihydrobenzo[ b ][1,4]dioxin-6-yl )-2-(1- methoxynaphthalen -4-yl)-1 H -phenanthro[9,10- d ]imidazole ( 2 ), and 1-(2,3-dihydrobenzo[ b ][1,4]dioxin-6 -yl )-2-(pyren-10-yl)-1 H-菲[9,10- d ]咪唑( 3）。由于 2 E _T1 > E _S1 ，在这些化合物中通过三重态-三重态湮没 (TTA) 过程将三重态上转换为单重态是主要的。基于芘基二氢苯并二恶英菲并咪唑( 3 )的非掺杂OLED表现出蓝色发射(450 nm)，CIE (0.15, 0.14)，亮度为53 890 cd m ^-2，功率效率为5.86 lm W ^-1，外量子效率为5.30 %，电流效率为 6.90 cd A ^-1。芘基二氢苯并二恶英菲并咪唑的高效器件性能是由于 TTA 对电致发光过程的贡献。