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Updated: Jul 31, 2026

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Hierarchically controllable photoreaction of a coordination polymer based on quaternized 1,2-bis(4'-pyridyl)ethylene
Li Sun1, Rui-Yun Guo, Xiao-Dong Yang
1MOE Key Laboratory of Cluster Science, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China. zhangjie68@bit.edu.cn.
Abstract:
A multiply photoactive compound has been developed based on quaternized 1,2-bis(4'-pyridyl)ethylene, which exhibits a hierarchical photoreaction by controlling light intensity. Weak ultraviolet light can effectively promote the cycloaddition reaction with fluorescence enhancement, while stronger ultraviolet light can stimulate a complex response of cycloaddition and electron-transfer which shows turn-off luminescence and coloration. Photofacilitated bleaching of the colored products has been observed for the first time in the pyridinium family.
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