化学学报 ›› 2022, Vol. 80 ›› Issue (3): 282-290.DOI: 10.6023/A21120556 上一篇    下一篇

研究论文

含不同烷基链四苯基丁二烯衍生物的聚集诱导发光及力致变色性能

张璐璐a, 王媛媛a, 朱贵楠b, 戴文博b, 赵紫璇a, 赵盈a, 支俊格a,*(), 董宇平b   

  1. a 北京理工大学 化学与化工学院 北京 100871
    b 北京理工大学 材料学院 北京 100871
  • 投稿日期:2021-12-12 发布日期:2022-01-22
  • 通讯作者: 支俊格
  • 基金资助:
    国家自然科学基金(21374010)

Aggregation-Induced Emission and Mechanochromism of the Tetraphenylbutadiene Derivatives Containing Different Alkyl Chains

Lulu Zhanga, Yuanyuan Wanga, Guinan Zhub, Wenbo Daib, Zixuan Zhaoa, Ying Zhaoa, Junge Zhia(), Yuping Dongb   

  1. a Beijing Institute of Technology, School of Chemistry and Chemical Engineering, Beijing 100871, China
    b Beijing Institute of Technology, School of Materials Science and Engineering, Beijing 100871, China
  • Received:2021-12-12 Published:2022-01-22
  • Contact: Junge Zhi
  • Supported by:
    National Natural Science Foundation of China(21374010)

设计合成了带有不同长度烷基链、不同极性取代基的四苯基丁二烯(TPB)衍生物TPB-COOCH3-1~6和TPB-COOH-1~6, 目标化合物均具有显著的聚集诱导发光(AIE)特性及较高的固态荧光量子效率. 烷基链长及取代基极性都会影响目标化合物在聚集时分子排列及分子运动的受限程度, 从而调控其AIE行为. 带有羧酸甲酯的TPB-COOCH3-1~6中, 丙基取代的TPB-COOCH3-3在四氢呋喃/水(THF/H2O)体系中荧光发射增强最为显著; 而羧基取代的TPB-COOH-1~6中, 因亲水性增加, 己基取代的TPB-COOH-6荧光强度增加的倍数最大; 并且, TPB-COOH系列化合物荧光增强的倍数明显低于相同烷基取代的甲酯衍生物TPB-COOCH3. 此外, 牛血清白蛋白、人血清白蛋白和带有羧基的AIE化合物掺杂时明显影响其固态时的发光及其力致变色性质, 尤其是研磨后会明显提高其荧光强度.

关键词: 聚集诱导发光, 四苯基丁二烯, 烷基链长度, 高荧光量子效率, 力致变色

Series of 1,1,4,4-tetraphenylbuta-1,3-diene (TPB) derivatives, named TPB-COOCH3-1~6 and TPB-COOH-1~6 containing different alkyl chains and polar substituents, were designed and synthesized by terminal alkyne dimerization and Pd-catalyzed cross-coupling, etc. The target compounds were characterized by 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, mass spectrum, Fourier transform infrared, from which satisfactory results to their molecular structures were obtained. They all have good thermal stabilities with high decomposition temperatures above 310 ℃ based on thermogravimetric analysis. Investigation of the photophysical properties indicated that the target compounds exhibited significant aggregation-induced emission (AIE) features with higher αAIE (αAIE=ΦPL,solid/ΦPL,solu) values of 20.5~49.6 for TPB-COOCH3-1~6 and 14.4~26.3 for TPB-COOH-1~6, and their photoluminescence quantum yields in solid state (ΦPL,solid) were determined as high as 71.3%~89.1% and 34.5%~73.2% for TPB-COOCH3-1~6 and TPB-COOH-1~6, respectively. The different lengths of alkyl chains and the polarity of the other substituent had obvious effect on the regular molecular stacking of the target compounds when they were forced to aggregate or precipitate, which affects the intermolecular interaction and the restriction degree of the rotators, consequently influenced their AIE behavior in the tetrahydrofuran (THF)/H2O mixtures. For the compounds TPB-COOCH3-1~6 containing methyl esters and different alkyl chains, TPB-COOCH3-3, which is with n-propyl, exhibited the most significant fluorescence enhancement (I/I0=26.0) in the THF/H2O mixtures. While, for TPB-COOH-1~6 containing -COOH and alkyl chains, TPB-COOH-6, which is with n-hexyl, had the maximum I/I0 (I/I0=15.7) due to the increase of hydrophilicity. Careful comparison revealed that the I/I0 and ΦPL,solid values of TPB-COOCH3-1~6 were higher than those of TPB-COOH-1~6 containing same alkyl chains under the same measuring condition, mainly attributing to the interaction between the -COOH groups or between -COOH and the polar solvent molecules, which increasing the nonradiative energy decay and weakening fluorescence emission. Furthermore, the incorporation of bovine serum albumin (BSA) and human serum albumin (HSA) into TPB-COOH significantly enhanced the solid-state fluorescence emission, and the BSA and HSA also influenced the mechanochromic properties of the AIEgens containing -COOH. Especially, the fluorescence intensity increased obviously after grinding the doped system of TPB-COOH-2 and BSA, mainly because the existence and steric hindrance of BSA molecules weakened the π-π interaction of the planarized TPB-COOH-2 molecules, which effectively inhibiting the intramolecular rotation of benzene ring and reducing the nonradia tive energy loss.

Key words: aggregation-induced emission, tetraphenylbutadiene, alkyl chains, high fluorescence quantum yield, mechanochromism