### 具有聚集态荧光增强性质的新型Tröger'sBase衍生物的合成与表征

1. 中国矿业大学化工学院 徐州 221000
• 收稿日期:2015-08-25 修回日期:2015-09-29 发布日期:2015-10-26
• 通讯作者: 韩相恩 E-mail:xiangenh@163.com
• 基金资助:

中央高校基本科研业务费专项基金(No. 2015XKZD08)资助项目

### Synthesis and Characteristics of Novel Tröger's Bases with the Properties of Aggregation-Induced Emission

Chu Yanhuan, Han Hui, Li Wei, Liu Zhentao, Han Xiang'en

1. China University of Mining and Technology, School of Chemical Engineering, Xuzhou 221000
• Received:2015-08-25 Revised:2015-09-29 Published:2015-10-26
• Supported by:

Project supported by the Fundamental Research Funds for the Central Universities (No. 2015XKZD08)

Tröger's bases (TB)具有特殊的刚性、立体Λ-型扭转构型, 理论上, 在分子堆积时其空间位阻作用不利于形成易引起“固态荧光淬灭”π-π密堆积, 可以有效改善有机发光材料中常见的由π-π密堆积引起的固态荧光淬灭现象. 选择Λ-型TB骨架作为分子的基本框架, 首先以溴代Λ-型TB为原料合成了醛基取代的TB, 再通过醛基-TB与取代苯乙腈类化合物经过简单的Knoevenagel缩合反应首次高效地合成了4个具有聚集态荧光增强特性的TB-氰基取代苯乙烯衍生物1a2a3a4a, 我们又通过钯催化的Heck偶联反应成功地将2-乙烯基噻吩引入到Λ-型TB中, 合成了结构对称的D-π-C-π-D型TB衍生物5a, 这些化合物均具有较大的Stokes位移. 所有产物均通过1H NMR, 13C NMR和HRMS等进行表征, 并详细地对这些化合物的光电物理性质等进行了深入的研究, 并重点探索验证了这些化合物的聚集诱导发光现象, 它们在掺水聚集过程中均表现出明显的聚集荧光增强的性质, 表明我们所合成的这些化合物均具有良好的聚集诱导发光性能(AIE). 通过测试化合物1a2a5a在不同溶剂中的紫外吸收光谱和荧光光谱, 表明化合物2a具有一定的溶剂效应, 且这3个化合物的荧光发射峰位置都随着溶剂极性不同而发生变化, 说明这些化合物存在着一定的ICT跃迁效应. 通过对这些化合物的初步探究, 希望这类新型固态发光TB衍生物能够在电致发光材料等领域具有潜在的应用价值.

Λ-shaped geometry configuration of Tröger's base (TB) is theoretically disadvantages to form π-π close stacking, which commonly results in fluorescence quenching in the solid state. A number of Λ-shaped cyano styrene based on Tröger's base (compounds 1a, 2a, 3a and 4a) was firstly developed with the structure of D-π-C-π-D which exhibited a typical aggregation-induced emission (AIE) behavior via Knoevenagel reaction with high yield. The thiophene ring was successful introduced into the Tröger's base skeleton firstly to obtain novel compound 5a with good solid luminescence via palladium-catalyzed Heck coupling reaction. The phenyl groups and thiophene ring were used as the electron donor and TB was used as a nucleus. All of these compounds were characterized and confirmed by 1H NMR, 13C NMR and MS spectra. All of the compounds were highly emissive in the condensed phase. In addition, compounds 1a, 2a, 3a and 4a were weakly fluorescent in solutions, but compound 5a exhibited blue emission strongly in solution, which revealed distinct aggregation-induced emission characteristics. The photo-physical properties of these compounds were studied in detail. We aimed at verifying the AIE properties of these compounds mainly. And the results showed a significant increase in fluorescence of these compounds with the addition of water, indicating that the synthesized compounds really have apparent AIE behavior. The solvent effect behavior was investigated to evaluate the effect of the solvent polarity on compounds 1a, 2a and 5a. Compound 2a showed some solvent effect, and all the emission peaks were red-shifted due to the increasing of the polarity of the solvents, indicating that a significant ICT effect existed in these compounds. In summary, in the process of the exploration of highly emissive organic solids, a new design strategy was presented and a new system of AIE materials was established. This study reveals that when constructing aggregation-induced emission molecules using substituent groups with expanded π-conjugation and introduction of appropriate steric hindrance on the substituent groups can restrict the formation of excimers effectively, hence achieving efficient solid state emission, which are expected to be used in electroluminescent field with potential value.