Xu Yincai, Wang Qingyang, Wei Jinbei, Peng Xiaomei, Xue Jianan, Wang Zhiheng, Su Shi-Jian, Wang Yue
State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China.
Angew Chem Int Ed Engl. 2022 Jul 25;61(30):e202204652. doi: 10.1002/anie.202204652. Epub 2022 Jun 7.
Multiple resonance thermally activated delayed fluorescence (MR-TADF) compounds have set off an upsurge of research because of their tremendous application prospects in the field of wide color gamut display. Herein, we propose a novel MR-TADF molecular construction paradigm based on polycyclization of the multiple resonance parent core, and construct a representative multiple resonance polycyclic aromatic hydrocarbon (MR-PAH) based on the para-alignment of boron and nitrogen atoms into a six-membered ring (p-BNR). Through the retrosynthesis analysis, a concise synthesis strategy with wide applicability has been proposed, encompassing programmed sequential boron esterification, Suzuki coupling and Scholl oxidative coupling. The target model molecule BN-TP shows green fluorescence with an emission peak at 523 nm and a narrow full-width at half-maximum (FWHM) of 34 nm. The organic light-emitting diode (OLED) employing BN-TP as an emitter exhibits ultrapure green emission with Commission Internationale de L'Eclairage (CIE) coordinates of (0.26, 0.70), and achieves a maximum external quantum efficiency (EQE) of 35.1 %.
多重共振热激活延迟荧光（MR-TADF）化合物因其在广色域显示领域的巨大应用前景而掀起了研究热潮。在此，我们基于多重共振母体核心的多环化提出了一种新型的MR-TADF分子构建范式，并通过将硼和氮原子对位排列成六元环（p-BNR）构建了一种具有代表性的多重共振多环芳烃（MR-PAH）。通过逆合成分析，我们提出了一种适用性广泛的简洁合成策略，包括程序化的顺序硼酸酯化、铃木耦合和肖尔氧化耦合。目标模型分子BN-TP呈现绿色荧光，发射峰位于523 nm，半高宽（FWHM）窄至34 nm。以BN-TP作为发光体的有机发光二极管（OLED）呈现出超纯绿色发射，国际照明委员会（CIE）坐标为（0.26, 0.70），并实现了35.1 %的最大外量子效率（EQE）。
