Chinese Journal of Organic Chemistry ›› 2023, Vol. 43 ›› Issue (9): 3287-3296.DOI: 10.6023/cjoc202302025 Previous Articles     Next Articles

氰基二苯乙烯桥联苯并菲二联体刺激响应盘状液晶: 合成、性质与应用

曾崇洋a, 胡平a, 汪必琴a, 方文彦b, 赵可清a,*()   

  1. a 四川师范大学化学与材料科学学院 四川成都 610066
    b 淮南师范学院化学与材料工程学院 安徽淮南 232038
  • 收稿日期:2023-02-23 修回日期:2023-04-10 发布日期:2023-05-05
  • 基金资助:
    国家自然科学基金(51773140); 国家自然科学基金(51973143)

Cyanostilbene Bridged Triphenylene Dyad Stimuli-Responsive Discotic Liquid Crystal: Synthesis, Properties and Applications

Chongyang Zenga, Ping Hua, Biqin Wanga, Wenyan Fangb, Keqing Zhaoa()   

  1. a College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066
    b School of Chemistry and Materials Engineering, Huainan Normal University, Huainan, Anhui 232038
  • Received:2023-02-23 Revised:2023-04-10 Published:2023-05-05
  • Contact: E-mail:
  • Supported by:
    National Natural Science Foundation of China(51773140); National Natural Science Foundation of China(51973143)

A dibranched cyanostilbene triphenylene dimer liquid crystal compound PBTPA with D-A structure was synthesized by the classical Knoevenagel and Suzuki coupling reaction, and characterized by nuclear magnetic resonance hydrogen spectrum (1H NMR) and carbon spectrum (13C NMR), and high resolution mass spectrometry (HRMS). PBTPA has excellent fluorescence emission in both solution and film states, showing obvious aggregation-induced emission enhancement effect, and the maximum fluorescence intensity is 4.2 times higher than the initial value. This effectively overcomes the drawbacks of aggregation-induced quenching of discotic molecules. PBTPA exhibits noticeable solvatochromic behavior from blue to orange in solvents with different polarities. The fluorescence emission wavelength is red-shifted by 110 nm, and the maximum absolute fluorescence quantum yield is as high as 74%. Density functional theory calculations show that there is outstanding charge transfer in PBTPA molecules. PBTPA has an obvious reversible grinding stimulation response. The fluorescence changes from yellow to orange before and after grinding. X-ray diffraction (XRD) and scanning electron microscope (SEM) prove that the process is accompanied by a crystal transformation. Based on this property, data rewriting paper can be designed easily with grinding and dichloromethane fuming, which can be used repeatedly by grinding and dichloromethane vapor fumigation. Additionally, PBTPA also has great liquid crystal properties, and polarizing optical microscopy (POM) texture appears apparently fan-shaped focal cone texture. With the change of temperature, it shows rectangular columnar phase to crystal phase, accompanied by fluorescence conversion, which is attributed to the change of viscosity and aggregation form. In addition, PBTPA is also a good electroluminescent material, and the color purity of yellow organic light-emitting diode prepared by PBTPA is as high as 99% at the turn-on voltage of 3.2 V. The highest luminous efficiency can reach 16 lm/W, so it has preeminent application potential in liquid crystal semiconductor, data processing, organic light emitting diode and other fields.

Key words: triphenylene, cyanostilbene, discotic liquid crystals, organic light-emitting diode (OLED), aggregation-induced emission (AIE), multi-stimuli responsive