化学学报 ›› 2025, Vol. 83 ›› Issue (1): 10-16.DOI: 10.6023/A24100296 上一篇    下一篇

研究论文

基于联二萘酚的手性有机发光分子合成与性能研究

张妞a, 韩书冉b, 马宏伟a, 陈磅宽b,*()   

  1. a 北京理工大学 分析测试中心 北京 102488
    b 北京理工大学 化学与化工学院 北京 102488
  • 投稿日期:2024-10-07 发布日期:2024-11-29
  • 基金资助:
    北京市自然科学基金(2232024); 北京理工大学实验室研究项目(2023BITSYB09)

Synthesis and Characterization of Chiral Luminescent Materials Based on Binaphthol Scaffolds

Niu Zhanga, Shuran Hanb, Hongwei Maa, Pangkuan Chenb()   

  1. a Analytical and Testing Center, Beijing Institute of Technology, Beijing 102488
    b School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488
  • Received:2024-10-07 Published:2024-11-29
  • Contact: *E-mail: pangkuan@bit.edu.cn
  • Supported by:
    Natural Science Foundation of Beijing(2232024); Experiment Based Project of BIT(2023BITSYB09)

集手性与发光性能于一体的手性光电材料是手性科学前沿研究领域之一. 本工作中, 设计并合成了三个具有手性发光特性的新型有机小分子化合物M1, M2M3, 这些分子的手性均来源于轴手性的联二萘酚骨架. 在联二萘酚手性单元的7,7'-位点进行结构修饰, 分别引入了二苯胺、对叔丁基二苯胺及叔丁基咔唑等电子给体(D)取代基. 三个手性分子的另一特征是它们都含有一个电子受体(A)基团, 即对苯二腈中心核结构. 通过核磁、高分辨质谱等手段对M1, M2M3进行了结构确认, 并通过吸收光谱、荧光发射光谱、电化学和密度泛函理论(DFT)计算的方法对其电子结构进行表征. 采用手性高效液相色谱法对它们的外消旋体进行手性拆分, 并通过圆二色光谱(CD)和圆偏振发光光谱(CPL)表征了光学对映体的手性光学性能. 由于分子内推拉电子结构的存在, 以上目标分子均展现出可逆的变温荧光响应性能.

关键词: 手性光学, 联二萘酚, 电子给/受体, 三芳基胺, 咔唑

The study of chiroptoelectronic materials that combine stereochemistry and luminescent properties represents one of the frontiers in areas of chirality science. Of particular interest is the access of organic chiral small molecules that can really show well-defined molecular structures and potentially unique structure-function relationships. In this article, we designed and synthesized three new examples of chiral luminescent compounds (M1, M2 and M3), where the axial chirality is derived from the incorporated binaphthyl groups. All these molecules feature an electron donor-acceptor (D-A) charge-transfer (CT) system, and they were prepared by palladium-catalyzed C—N coupling reactions between the electron-donating carbazole or biarylamines and binaphthyls that were further reacted with 2,3,5,6-tetrafluoro-1,4-dicyanoben- zene as a strong electron-accepting moiety. The structures of M1, M2 and M3 have been verified by 1H, 13C NMR and high-resolution mass spectrometry. Their electronic properties were characterized by UV-vis absorption and emission spectra as well as density functional theory (DFT) calculations. The electrochemistry has been performed by cyclic and differential pulse voltammetry, which showed reversible oxidations on the electron donor sites. The enantiomers of these chiral molecules synthesized here were optically resolved through chiral high performance liquid chromatography (HPLC) with a high value of enantiomeric excess (ee>98%), and the chiroptical properties in the ground and excited states were investigated by circular dichroism (CD) and circularly polarized luminescence (CPL) spectra, respectively. Our computations disclosed a small singlet-triplet energy gap (∆ES-T), and the experimental results gave rise to an enhanced charge-transfer emission behavior with increasing temperature, likely indicating the potential applications in thermally activated delayed fluorescent (TADF) materials. Solvatochromic emissions have been observed for all the molecules as changes in solvent polarity due to the intramolecular charge-transfer effects. Emission color changes were also reversibly induced in solutions in response to changes in temperature, as a result of stabilization of CT states by the temperature-dependent polarity of solvents.

Key words: chiroptics, binaphthol, electron donor-acceptor, triarylamine, carbazole