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Updated: Nov 20, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Luminescent silver(i) complexes with pyrazole-tetraphenylethene ligands: turn-on fluorescence due to the
Zou-Hong Xu1, Zi-Qing Huang, Xiao-Hui Liu
1Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing National Laboratory of Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China. sunwy@nju.edu.cn.
Abstract:
A new tetrapyrazole-modified tetraphenylethene (TPE) ligand L was designed and found to display "turn-on" fluorescence when it combines with Ag+ ions in dilute solution by restricting intramolecular rotation of TPE. A series of Ag complexes 1-7 were obtained, and they exhibit excellent fluorescence properties in the solid state. Compared with PF6-, the silver complex with the CF3SO3- anion can further enhance its fluorescence due to the transformation of its structure from Ag2L (2) to Ag4L2 (3). As zero-dimensional complexes, 1 and 3 have excellent piezochromic properties with a color change from blue to green. Furthermore, structural changes of 1 and 3 to the corresponding three-dimensional frameworks 4 and 5 occur upon immersing in ethanol. In addition, 1 can act as a potential fluorescent probe for sensing nitrile compounds.
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