Orange-red thermally activated delay fluorescence emitters based on asymmetric difluoroboron chelated enaminone: Impact of donor position on luminescent properties
摘要:
Asymmetric enaminone difluoroboron complexes (BFs) exhibit highly solid emission and appropriated electron-accepting properties, whereas the position of the substituents has a significant influence on their optical properties due to the structural asymmetry. In this work, we employed BF as acceptor and 9,9-dimethylacridine (DMAC) as donor to construct two thermally activated delay fluorescence (TADF) molecules DMAC-BF and BF-DMAC, in which DMAC unit was set on the B-O and B-N sides of BF, respectively. DMAC-BF and BF-DMAC exhibited the broad orange-red emission bands in toluene, while they emitted yellow and red fluorescence in solid state, respectively. The photoluminescence quantum yield (PLOY) of DMAC-BF (52%) is higher than that of BF-DMAC (29%), owing to its lower nonradiative decay rate. Solution-processed organic light-emitting diode (OLED) devices based on both of DMAC-BF and BF-DMAC exhibited orange-red electroluminicence spectra. Owing to its higher photoluminescence quantum yield, DMAC-BF-based OLED exhibited better electroluminicence performance with a maximum current efficiency of 24.9 cd/A, a maximum power efficiency of 23.0 lm/W, and a maximum EQE of 11.3%.
Features of reactions of (E)-1-(β-aroylvinyl)pyridinium bromides with binucleophiles
摘要:
Regardless of pH and a solvent nature the reactions of (E)-1-(beta-aroylvinyl)pyridinium bromides with hydrazine led to the formation of pyrazole derivatives. The salts reacted with thiourea via intermediate formation of 4-arylpyrimidine-2-thiol to give (Z)-2-[(beta-aroylvinyl)sulfanyl]-4-arylpyrimidines. In the case of N,N'-diphenylthiourea the reaction provided 6-aryl-3-aroyl-1-phenylpyridinium bromides. Pyridine hydrobromide liberated in the reaction course has a major influence on the process chemoselectivity.
Palladium-Catalyzed Intermolecular Oxidative Coupling Reactions of (<i>Z</i>)-Enamines with Isocyanides through Selective β-C(sp<sup>2</sup>)-H and/or C=C Bond Cleavage
two efficient palladium‐catalyzed intermolecular oxidative couplingreactions of (Z)‐enamines with isocyanides via selective β‐C(sp2)‐H and/or C=C bond cleavage have been developed, leading to controllable chemodivergent and stereoselective construction of a wide range of (E)‐β‐carbamoylenamine derivatives containing strong intramolecular hydrogen bonds. Furthermore, possible reaction pathways for these
Orange-red thermally activated delay fluorescence emitters based on asymmetric difluoroboron chelated enaminone: Impact of donor position on luminescent properties
作者:Hua Li、Haiyang Shu、Xin Wang、Xiaofu Wu、Hongkun Tian、Hui Tong、Lixiang Wang
DOI:10.1016/j.dyepig.2020.108810
日期:2021.1
Asymmetric enaminone difluoroboron complexes (BFs) exhibit highly solid emission and appropriated electron-accepting properties, whereas the position of the substituents has a significant influence on their optical properties due to the structural asymmetry. In this work, we employed BF as acceptor and 9,9-dimethylacridine (DMAC) as donor to construct two thermally activated delay fluorescence (TADF) molecules DMAC-BF and BF-DMAC, in which DMAC unit was set on the B-O and B-N sides of BF, respectively. DMAC-BF and BF-DMAC exhibited the broad orange-red emission bands in toluene, while they emitted yellow and red fluorescence in solid state, respectively. The photoluminescence quantum yield (PLOY) of DMAC-BF (52%) is higher than that of BF-DMAC (29%), owing to its lower nonradiative decay rate. Solution-processed organic light-emitting diode (OLED) devices based on both of DMAC-BF and BF-DMAC exhibited orange-red electroluminicence spectra. Owing to its higher photoluminescence quantum yield, DMAC-BF-based OLED exhibited better electroluminicence performance with a maximum current efficiency of 24.9 cd/A, a maximum power efficiency of 23.0 lm/W, and a maximum EQE of 11.3%.
Features of reactions of (E)-1-(β-aroylvinyl)pyridinium bromides with binucleophiles
作者:R. Dzh. Khachikyan、Z. G. Ovakimyan、G. A. Panosyan、R. A. Tamazyan、A. G. Ayvazyan
DOI:10.1134/s1070363216070070
日期:2016.7
Regardless of pH and a solvent nature the reactions of (E)-1-(beta-aroylvinyl)pyridinium bromides with hydrazine led to the formation of pyrazole derivatives. The salts reacted with thiourea via intermediate formation of 4-arylpyrimidine-2-thiol to give (Z)-2-[(beta-aroylvinyl)sulfanyl]-4-arylpyrimidines. In the case of N,N'-diphenylthiourea the reaction provided 6-aryl-3-aroyl-1-phenylpyridinium bromides. Pyridine hydrobromide liberated in the reaction course has a major influence on the process chemoselectivity.