Spiro-Functionalized Diphenylethenes: Suppression of a Reversible Photocyclization Contributes to the Aggregation-Induced Emission Effect

Zhibiao Zhou; Sheng Xie; Xian Chen; Yujie Tu; Jiannan Xiang; Jianguo Wang; Zikai He; Zebing Zeng; Ben Zhong Tang

doi:10.1021/jacs.9b04426

Spiro-Functionalized Diphenylethenes: Suppression of a Reversible Photocyclization Contributes to the Aggregation-Induced Emission Effect

J Am Chem Soc. 2019 Jun 26;141(25):9803-9807. doi: 10.1021/jacs.9b04426. Epub 2019 Jun 18.

Authors

Zhibiao Zhou¹, Sheng Xie², Xian Chen¹, Yujie Tu², Jiannan Xiang¹, Jianguo Wang^{2

3}, Zikai He⁴, Zebing Zeng¹, Ben Zhong Tang^{2

5}

Affiliations

¹ State Key Laboratory of Chemo/Biosensing and Chemometrics, Center for Aggregation-Induced Emission, College of Chemistry and Chemical Engineering , Hunan University , Changsha 410082 , China.
² Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Institute for Advanced Study and HKUST-Shenzhen Research Institute, The Hong Kong University of Science & Technology , Hong Kong , China.
³ College of Chemistry and Chemical Engineering , Inner Mongolia University , Hohhot 010021 , China.
⁴ School of Science , Harbin Institute of Technology, Shenzhen, HIT Campus of University Town , Shenzhen 518055 , China.
⁵ Center for Aggregation-Induced Emission, SCUT-HKUST Joint Research Institute, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640 , China.

PMID: 31204478
DOI: 10.1021/jacs.9b04426

Abstract

Many aggregation-induced emission (AIE) materials are featured by the diphenylethene (DPE) moiety which exhibits rich photophysical and photochemical activities. The understanding of these activities behind AIE is essential to guide the design of fluorescent materials with improved performance. Herein by fusing a flexible DPE with a rigid spiro scaffold, we report a class of novel deep-blue material with solid-state fluorescent quantum yield (Φ_F) up to 99.8%. Along with the AIE phenomenon, we identified a reversible photocyclization (PC) on DPE with visible chromism, which is, on the contrary, popularized in solutions but blocked by aggregation. We studied the steric and electronic effects of structural perturbation and concluded that the PC is a key process behind the RIMs (restriction of intramolecular motions) mechanism for these materials. Mitigation of the PC leads to enhanced fluorescence in solutions and loss of the AIE characteristics.

Publication types

Research Support, Non-U.S. Gov't