Huang Ze, Ding Aixiang, Yang Jiaxiang, Wang Chengyuan, Tang Fang
College of Chemistry and Chemical Engineering, Key Laboratory of Structure and Functional Regulation of Hybrid Materials, Ministry of Education, Photoelectric Conversion Energy Materials and Devices Key Laboratory of Anhui Province, Anhui University, Hefei, 230061, P.R. China.
The Institute of Flexible Electronics (IFE, Future Technologies), Xiamen University, Xiamen, 361005, P. R. China.
Chemistry. 2023 Apr 25;29(24):e202203628. doi: 10.1002/chem.202203628. Epub 2023 Mar 20.
Dual-state emission luminogens (DSEgens) are receiving research interest in the construction of multifunctional materials due to their inherent advantage of high emission efficiency in both the molecularly dispersed solution state and the solid state. However, it remains challenging in synthesizing DSEgens via a delicate manipulation of the molecular structures. This work presents an example of bright DSEgen synthesis by tuning the molecular electronic structures and conformations. Three coumarin-tetraphenylethylene (TPE) molecules with a donor-acceptor electronic structure and highly twisting conformations have been synthesized. While compound resulting from direct conjugation of coumarin with a TPE unit shows aggregation-induced emission, compound with an N,N-diaminoethyl modification on the 7-position of coumarin and compound with a further phenyl linker between coumarin and TPE units feature strong dual-state emission. Benefiting from their strong solid emission and twisting conformations, these fluorophores display reversible mechanofluorochromism. Finally, applications for rewritable information storage in the solid state and live-cell imaging in the solution state were demonstrated.
双态发射发光体（DSEgens）因其在分子分散溶液态和固态中均具有高发射效率这一固有优势，在多功能材料的构建方面正受到研究关注。然而，通过对分子结构进行精细调控来合成DSEgens仍然具有挑战性。这项工作展示了一个通过调节分子电子结构和构象来合成明亮DSEgen的实例。合成了三个具有供体-受体电子结构和高度扭曲构象的香豆素-四苯乙烯（TPE）分子。虽然香豆素与TPE单元直接共轭得到的化合物表现出聚集诱导发光，但在香豆素7位具有N，N-二氨基乙基修饰的化合物以及在香豆素和TPE单元之间有进一步苯基连接基的化合物具有强烈的双态发射。得益于其强烈的固态发射和扭曲构象，这些荧光团表现出可逆的机械荧光变色特性。最后，展示了其在固态可重写信息存储和溶液态活细胞成像方面的应用。
