Calixarenes是酚和甲醛於鹼性溶液中，進行催化聚合反應而得到的環狀聚合產物，因其分子內具有杯形中空的結構型狀，所以可以藉由此結構特性與一些小型的有機分子或金屬離子產生嵌合的現象，進而形成“主-客化合物”，這種嵌合特性可應用於微量檢驗、離子分離和酵素模擬的研究上。本論文主要的目的為合成出對位羥基取代之calix[4]arene 及其乙醯酯化的衍生物。
在鹼性條件的催化下，p-tert-butylphenol 與甲醛溶液，可聚合得到黃綠色的固態前驅物，將此聚合前驅物置於二苯醚 (diphenyl ether)中進行迴流，可被轉換成 p-tert-butylcalix[4]arene (1)；如再以三氯化鋁 (AlCl3) 作為催化劑，進行反向的 Friedel-Crafts 反應來移除環狀聚合物上的對位三級丁基，便可得到對位無取代之 calix[4]arene (6)。
過去本實驗室的研究發現，calix[4]arene 與過量的benzoyl chloride在pyridine中進行酯化反應時，可一步製備出三苯甲酸酯化的calix[4]arene 26；若將所得到之三苯甲酸酯化calix[4]arene 在pH 7 的緩衝溶液中，進行非均勻相的ClO2 氧化反應，可得到三苯甲酸酯化的calix[4]monoquinone 27；calix[4]monoquinone 27 可在Na2S2O4 的水溶液中進行非均勻相的還原，而得到苯醌官能團被還原的三苯甲酸酯化p-monohydroxycalix[4]arene 28。
三苯甲酸酯化p-monohydroxycalix[4]arene 28分子中，氫苯醌的上緣羥基，因立體障礙較小，可利用乙醯氯在 pyridine中進行乙醯酯化，來產生單乙醯酯化衍生物 29；但下緣的羥基，則必需使用反應性更好的乙醯氯與AlCl3 在二氯甲烷的反應條件，來製備雙乙醯酯化的衍生物 30。
這些合成的研究過程中之產物皆利用1H-NMR、13C-NMR及COSY的分析來鑑定，在本論文中對合成和鑑定的過程均會做敘述與討論。
Calixarenes, which are cyclic oligomers of p-substituted phenols and formaldehyde , are able to include small organic molecules or metal ions within the molecular cavities to form“ host-guest”complexes. These phenomena have been proposed in the applications of micro-analysis, ion separation, and enzyme-mimic studies. The main purpose of this thesis is to study the synthesis of p-hydroxycalix[4]arene and its acetate derivatives.
In the basic conditions, p-tert-butylphenol were polymerized with formaldehyde to form a yellowish precursor. Refluxing of this precursor in diphenyl ether yielded the p-tert-butylcalix[4]arene (1). The AlCl3 catalyzed reverse Friedel-Crafts reaction were then applied to remove the p-tert-butyl groups and gave parent calix[4]arene (6).
It was known that the benzoylation of calix[4]arene in pyridine yielded only the tribenzoated product 26. The tribenzoated product was able to convert to the corresponding calix[4]monoquinone 27 by chlorine dioxide oxidation process. The quinone moiety of the compound 27 was reduced in heterogeneous system by aqueous sodium hydrosulfite solution and yielded the corresponding 5-hydroxycalix[4]arene tribenzoate 28. The less steric hindrance 5-hydroxy group of compound 28 was acetylated with acetyl chloride in pyridine to yield monoacetated product 29. Whereas, the “lower rim” hydroxyl group was acetylated with acetyl chloride in methylene chloride with the presence of AlCl3 as catalyst and afforded the diacetate product 30.
All the new products which were produced in this thesis were characterized by 1H-NMR, 13C-NMR, and COSY. The synthetic procedure for p-monohydroxycalix[4]arene and its acetate derivatives were also discussed in this thesis.
