| Summary: | 碩士 === 國立交通大學 === 應用化學系碩博士班 === 102 === In recent years, calix[4]arene derivatives have been extensively studied in supramolecular gel formation. Although they can be used in ions recognition and oil spill recovery, they usually form one component gels. Two component gel formation of calix[4]arene was not known until Prof. Zheng’s work published in 2007. It worth noting that there have been few reports on using halogen bonding as intermolecular forces for gel formation. In this thesis, we used click chemistry reaction to synthesize triazolyl-pyridyl substituted calix[4]arene derivatives 33 , which was found to form a one component gel in ethanol and it minimum gelation concentration was determined to be 30 mM.
Using calix[4]arene derivatives 33 as host and dicarboxyl, tricarboxyl, diiodo, or triiodo substituted aromatic derivatives in ethanol as bridge, we found that they formed two component gel through different intermolecular interactions. The morphology of hydrogen bonding-triggered two component gel can be nanotube, fiber or rod; whereas halogen bonding-triggered two component gel can be fiber or sheet. In addition to the two component gel with aromatic derivatives, they could also form metallogels when compound 33 mixed with calcium, mercury, lithium and sodium ions in ethanol. The morphology of these metallogels were found to be rod, slender fibrous, stubby-type fibrous and nanotubes. Substantially lower the minimum gelation concentration of compound 33 can be achieved which decreased from 30 mM to 6 mM. As analyzed by ICP-MS, the two component gelation of 33 with Hg2+ can effectively remove the mercury content in ethanol by 99.6%.
In addition, we wish to modify the upper rim of 27 by substituting the t-butyl by isoaryl group so that it can control the diameter of the micro spherical gels. During the synthesis, we found that compound 44 was difficult to be purified. Although we could obtain a single crystal from the reaction, we could not understand why its 1H NMR spectrum was still complicated. We used the mixture 44 to further functionalize it to propargloxy calix[4]arene 45 and subsequent bis-1,3-dipolar cycloaddition reaction to get 49; however, we found that they are still mixtures of compounds based on TLC analysis. We need to work on the purification
procedures of compound 44 in the future.
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