Xu Yongqiang, Ni Zhigang, Xiao Yao, Chen Ziwei, Wang Sisi, Gai Lizhi, Zheng You-Xuan, Shen Zhen, Lu Hua, Guo Zijian
College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, and Key Laboratory of Organosilicon Material Technology of Zhejiang Province, Hangzhou Normal University, Hangzhou, 311121, China.
State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
Angew Chem Int Ed Engl. 2023 Feb 13;62(8):e202218023. doi: 10.1002/anie.202218023. Epub 2023 Jan 18.
It is essential to create organic compounds that exhibit circularly polarized luminescence (CPL) in the near-infrared (NIR) range. Helicene-type emitters possess appealing chiroptical features, however, such NIR molecules are scarce due to a paucity of synthetic strategies. Herein, we developed a series of helical β-isoindigo-based B-O-B bridged aza-BODIPY analogs that were synthesized conveniently. The reaction of diimino-β-isoindigo with a heteroaromatic amine produced a restricted ligand cavity, which triggered off the generation of a B-O-B bridge. The B-O-B bridge led to distorted conformations that satisfy the helical requirements, resulting in excellent spectroscopic and chiroptical properties. Tunable CPL with the highest luminescence dissymmetry factor (g ) of 1.3×10 and a CPL brightness (B =11.5 M cm ) in the NIR region was achieved. This synthetic approach is expected to offer a new opportunity to chiral chemistry and increase flexibility for chiroptical tuning.
合成在近红外（NIR）范围内具有圆偏振发光（CPL）的有机化合物至关重要。螺旋烯型发光体具有吸引人的手性光学特性，然而，由于合成策略有限，这类近红外分子很少见。在此，我们开发了一系列基于螺旋β-异吲哚并二酮的B-O-B桥连氮杂硼二吡咯类似物，其合成简便。二亚氨基-β-异吲哚并二酮与杂芳胺的反应产生了受限的配体腔，从而引发了B-O-B桥的生成。B-O-B桥导致了满足螺旋要求的扭曲构象，从而产生了优异的光谱和手性光学性质。在近红外区域实现了可调谐的CPL，其最高发光不对称因子（g）为1.3×10，CPL亮度（B = 11.5 M cm）。这种合成方法有望为手性化学提供新的机会，并增加手性光学调谐的灵活性。
