摘要
以对叔丁基苯酚和甲醛水溶液为起始原料,经过环化缩聚、脱叔丁基、氯甲基化三步反应,最后与2-甲基-6-叔丁基苯酚进行亲核取代反应,合成了不对称酚型杯[n]芳烃4a(n=4)和4b(n=6),表征了它们的结构,并确认了4a中杯环为锥体构象。
Clixarene, as a class of special cyclic hindered phenols, have displayed good performance in polymer stabilization towards light, heat, oxygen and radiation. In the present paper,two new calixarene derivatives - unsymmet-rically hindered phenol - substituted calix[n]arene 4a ( n = 4) and were 4b ( n = 6) were synthesized with p - tert -butylphenol and aqueous formaldehyde as starting materials via cyclic condensation, de - ten - butylation, chloromethy-lation, and nucleophilic substitution with 2 - ten - bytyl - 6 - methylphenol. Their structures were established by IR, MS, UV, and 1H NMR spectra oscopy, and elemental analysis 4a was assigned to be in the cone conformation. Introduction of unsymmetrical structure into the calixarene results in decrease in melting point to ca. 100℃. This is advantageous to the polymer processing and provides a new way to design calixarene stabilizers. Preliminary results of the antioxi-dant activities show that unsymmetrically hindered phenols - substituted calix[n]arenes exhibit a higher stoichiometric factor (4.8) compared to calixarene with symmetrical phenol stricture (4.2) and a much higher factor to small phenol compound such as 2 - ten - bytyl - 6 - methylphenol (1.4) and 2, 6 - di - tert - butyl - 6 - methyl phenol (2.0).
出处
《有机化学》
SCIE
CAS
CSCD
北大核心
2000年第5期836-839,共4页
Chinese Journal of Organic Chemistry
基金
国家自然科学基金(项目编号:No.29602005)
关键词
不对称酚
杯芳烃
合成
抗氧剂
稳定剂
unsymmetrical hindered phenol, calixarene, synthesis
