The Studies in the Synthesis of exo-Calix[4]arenes

• Main Authors: Ching-Yu Tso, 左清宇
• Other Authors: Lee-gin Lin
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/50695364261052110988

碩士 === 中國文化大學 === 應用化學研究所 === 87 === 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 the "host-guest complexes". This phenomenon has been proposed in the research area of micro-analysis detection devices, ion separation and enzyme-mimic studies. The main purpose of this thesis is developing a new synthetic method for a new type of calixarenes, the exo-calix[4]arene system. Condensation of p-tert-butylphenol with formaldehyde under basic conditions afforded an yellowish precursor, and the precursor were then converted to p-tert-butylcalix[4]arene by refluxing in diphenyl ether. The tert-butyl group of p-tert-butylcalix[4]arene was removed via reverse Friedel-Crafts reaction to yield the parent calix[4]arene in moderate yield. Treatment of calix[4]arene with benzoyl chloride in pyridine yield only tribenzoate 24, which were converted to the corresponding calix[4]quinone 25 upon oxidized with ClO2. The "upper rim" carbonyl group of compound 25 was protected with ethylene glycol and gave the partial mono-ketal derivative 26. The benzoate protecting groups were cleavaged under basic conditions to yield calix[4]quinone-ethylene ketal 27, and the ketal protecting groups were then removed in acidic conditions to give calix[4]monoquinone 28. When compounds 26 or 27 were reduced by following Wolff-Kishner reaction conditions, only the partial reduced tetrahydroxycalix[4]arene-ethylene ketal 29 was isolated as an unexpected product. The same reaction would also partially reduce compound 25 to the corresponding pentahydroxy-calix[4]arene 30 in 67% yield. When compounds 27 and 28 were treated with 2,4-DNP, the same product 31 was producted. This result is due to the ketal moieties in compound 27 was easily hydrolyzed to compound 28 under the reaction reactions. Treatment of compounds 25, 27 and 28 with p-nitrophenylhydrazine solution produced the same resulted, the corresponding p-arylazo substituted calix[4]arenes 32 and 33 were afforded respectively. All products which prepared in this thesis were characterized by 1H-NMR and FAB-MS, and the synthetic procedure were discussed in detail.