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Updated: Jul 19, 2025

Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Effect on the conformation of monosubstituted pillar[5]arene: solvent, temperature, concentration and linker length
Zhen Fu1, Yanqing Jin1, Bingqian Xie1
1Key Laboratory for Green Chemical Process of Ministry of Education, School of Chemical Engineering & Pharmacy, Wuhan Institute of Technology, 693 Xiongchu Avenue, Wuhan 430073, P. R. China. witty_lau@hotmail.com.
Abstract:
A series of monosubstituted pillar[5]arenes (PIn) bearing a fluorescent probe (E)-4-[4-(dimethylamino)styryl-]-1-pyridinium were synthesized and characterized. The conformations of the monosubstituted pillar[5]arenes were investigated systematically by NMR and fluorescence spectroscopy and were found to be dependent on solvent polarity, concentration, temperature and linker length. PI1 with a short linker remained uncomplexed in DMSO, whereas it formed a polymer at high concentration in chloroform. As the linker length increased, PI2-4 could exist in equilibrium between self-inclusion monomer and intermolecular complexes. The increase of concentration led to the formation of a polymer in DMSO and a self-penetrating dimer in chloroform. The results provided information on the modulation of supramolecular assemblies by various factors.
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