Synthesis of a Series of Calix[6]arenePolymers fromp-ter-butylphenol
Keywords:
p-tert-butylphenol, p-tert-buthylcalix[6]arene, esterification, hydrolysis, andpolypropyl-calix[6]arenesAbstract
A research has been conducted to synthesize ofa series of novel calix[6]arene -based polymers 2a-cusing p-tert-butylphenol as a starting material. It was of interest to study calix[6]arene and its derived polymers which have cavity size larger than calix[4]arene.The synthesis was carried out in several steps i.e (1) formation of p-tert-butylcalix[6]arene from p-tert-butylphenol, (2) treatment of p-tert -butylcalix[6]arene with allyl bromide under alkaline condition to yield compound 1a, (3) esterification of 1a to yield 1b, (4) hydrolysis of 1b with chloride acid to yield 1c and (5) polymerization of 1a-cby treatment with concentrated sulfuric acid to yield a series of polypropyl-calix[6]arenes2a-c. The structures of those products were observed by means of melting point, FTIR and 1H NMR spectrometers. The 1H NMR spectra showed that one allyl group had been incorporated to the lower rim of the p-tert-butylcalix[6]arene.The polymers 2a-cwereobtained as brownish crystals with the melting point of 199-201; 99-101; and 101-103 oC respectively. With a tunnel-like structure of the polymers, they can be usedas adsorbents to trap heavy metal ions.