25603-67-2Relevant articles and documents
The first ESR observation of radical species in subcritical water
Kobiro, Kazuya,Matsura, Masahiko,Kojima, Hiroyuki,Nakahara, Koichi
, p. 807 - 810 (2009)
Triphenylmethanol was treated in subcritical and supercritical water. A radical species, triphenylmethyl radical, was directly generated from triphenylmethanol in subcritical and supercritical water without using any radical initiator. The radical formati
-
Bottaro
, p. 990 (1978)
-
Novel multifunctional fluorene-phenanthroimidazole hybrid materials: Non-doped near-ultraviolet fluorescent emitter and host for green phosphorescent OLEDs
Chi, Hai-Jun,Guan, Hui-Min,Hu, Yong-Xu,Hu, Zhi-Zhi,Li, Xiao,Lv, Yan-Li,Xiao, Guo-Yong,Xie, Dong-Dong,Zhang, Dong-Yu
, (2020/12/07)
Deep-blue-emissive host materials are crucial to achievement of high-performance full-color organic light-emitting diodes (OLEDs), simplifying the manufacturing process and reducing production costs. To develop efficient deep-blue-emissive host materials is still challenging. By incorporating 9,9-diphenylfluorene moiety into phenanthroimidazole via the insulating N1 position of imidazole, two fluorene-phenanthroimidazole hybrid near-ultraviolet-emitting materials FL-PI and FL-BPI were designed and synthesized. The photophysical property, thermal and amorphous ability, electrochemical property and electron structure could be effectively regulated by molecular design strategy. Both FL-PI and FL-BPI exhibited moderate near-ultraviolet emission (0.50/0.63), high triplet energy level (2.58/2.57eV), high thermostability (Td: 371/542 °C; Tg: 134/210 °C) and carrier-transporting nature. Non-doped near-ultraviolet OLEDs adopting FL-BPI emitter showed the maximum efficiencies of 5.4%, 3.8 cd A?1 and 2.8 lm W?1 with the CIE coordinates of (0.15, 0.05). In addition, FL-PI/FL-BPI-hosted green phosphorescent OLEDs demonstrated the maximum efficiencies of 16.3%, 28.8 cd A?1, 21.1 lm W?1 and 21.1%, 75.3 cd A?1, 27.8 lmW?1, respectively. Moreover, the external quantum efficiencies of FL-PI/FL-BPI-hosted green phosphorescent devices remained as high as 16.1% and 21.0% at 1000 cd m?2. This work demonstrates that the strategy for the development of near-ultraviolet high-emissive host materials is feasible.
The p: K a values of N-aryl imidazolinium salts, their higher homologues, and formamidinium salts in dimethyl sulfoxide
Cole, Marcus L.,Dunn, Michelle H.,Harper, Jason B.,Konstandaras, Nicholas,Luis, Ena T.
supporting information, p. 1910 - 1917 (2020/03/23)
A series of imidazolinium salts, their six-, seven- A nd eight-membered homologues, and the related formamidinium salts were prepared, and their pKa values were determined in DMSO at 25 °C using the bracketing indicator method. The effect of each type of structural variation on the acidity of each salt was considered, particularly noting the importance of ring size and the effect of the steric and electronic nature of the N-aryl substituents. The effect of a cyclic structure was also probed through comparing the cyclic systems with the corresponding formamidinium salts, noting the importance of conformational flexibility in the latter cases. Along with allowing choice of appropriate bases for deprotonation of these species, it is anticipated that the data presented will aid in the understanding of the nucleophilicity, and potentially catalytic efficacy, of the corresponding carbenes.
