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Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Acid/base responsive pseudo[3]rotaxanes from amine naphthotubes and bis-pyridinium/isoquinolinium guests
Li-Shuo Zheng1, Hao Nian1, Song-Meng Wang1
1Department of Chemistry, Southern University of Science and Technology, Xueyuan Blvd 1088, Shenzhen 518055, China.
Abstract:
A novel cooperative pseudo[3]rotaxane system was successfully constructed by the inclusion complexation of two identical amine naphthotubes with a bis-pyridinium/isoquinolinium guest. Single crystal structure analysis revealed that weak Csp-H⋯O hydrogen bonds between the two hosts are responsible for the positive cooperativity during the formation of pseudo[3]rotaxanes. Moreover, intermolecular charge-transfer interactions between the electron-rich host and the electron-poor guests were observed. The pseudo[3]rotaxanes showed pH-controllable association/dissociation processes with naked-eye color changes in solution.
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