Tian Xinyu, Fan Zengming, Li Zeyi, Zhang Shitong, Li Zhiqiang, Zhuang Xuming, Wang Yue, Dou Chuandong
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
Jihua Laboratory, Foshan, 528200, P. R. China.
Angew Chem Int Ed Engl. 2025 Apr 17;64(17):e202500110. doi: 10.1002/anie.202500110. Epub 2025 Feb 21.
Control over molecular topologies and/or heteroatom doping of polycyclic aromatic hydrocarbons (PAHs) may alter their electronic structures and achieve desirable physical properties. Herein, this work challenges boron-doping and edge-transformation of π-extended PAHs. We successfully synthesized a series of large-size PAHs featuring a boron-doped zigzag/armchair edge topology through one-pot multifold Scholl cyclization reaction. Two of them possess the desired C-symmetric and unexpected unsymmetrical CB nanographene frameworks, respectively, thus illustrating triply boron-edging manipulations of hexa-peri-hexabenzocoronene. Detailed studies reveal that such boron-doped edge topology significantly inhibits their excited-state molecular vibrations and thereby produces narrowband emission characteristics. The full width at half maximum (FWHM) values of their fluorescence spectra are as small as 12-18 nm, which have never been observed for pristine boron-doped π-system and are among the smallest values reported for organic emitters. Their solution-processed organic light-emitting diodes (OLEDs) display extremely narrowband electroluminescence, and additionally, the obtained FWHM of only 23 nm represents the narrowest one reported for red OLEDs.
对多环芳烃（PAHs）的分子拓扑结构和/或杂原子掺杂进行控制，可能会改变其电子结构并实现理想的物理性质。在此，这项工作对π扩展PAHs的硼掺杂和边缘转变提出了挑战。我们通过一锅多步肖尔环化反应成功合成了一系列具有硼掺杂锯齿形/扶手椅形边缘拓扑结构的大尺寸PAHs。其中两种分别具有所需的C对称和意想不到的不对称CB纳米石墨烯框架，从而说明了六并六苯的三重硼边缘操纵。详细研究表明，这种硼掺杂边缘拓扑结构显著抑制了它们的激发态分子振动，从而产生窄带发射特性。它们荧光光谱的半高宽（FWHM）值小至12 - 18 nm，这在原始硼掺杂π体系中从未观察到，并且是有机发光体报道的最小值之一。它们通过溶液处理的有机发光二极管（OLED）显示出极窄带的电致发光，此外，仅23 nm的FWHM是红色OLED报道中最窄的。
