Abstract: 3-n-butyl-6-(1-decyl olefinic acid base)-4-cyclohexene diacid (C22 tricarboxylic acid) was prepared with tung oil as raw material through the steps of transesterification reaction with methanol，Diels-Alder reaction with maleic anhydride，saponification and acidification sequentially. The structure of the C22 tricarboxylic acid was characterized by FT-IR spectroscopy，MS and 1H NMR. The optimal reaction condition was determined by orthogonal experiment，as follows：α-eleostearic acid methyl ester and maleic anhydride feed ratio of 1∶1.2，reaction temperature 160 ℃，reaction time is 2 hours.

Key words: tung oil, maleic anhydride, Diels-Alder reaction, C22 tricarboxylic acid

摘要： 以桐油为原料制备3-正丁基-6-(1-癸烯酸基)-4-环己烯二酸，分子式为C22H34O6（C22三元羧酸）。首先通过酯交换反应得到桐油酸甲酯，桐油酸甲酯与马来酸酐经过Diels-Alder反应制备3-正丁基-6-(1-癸烯酸甲酯基)-4-环己烯二酸，再经过皂化、酸化和分离等过程得到C22三元羧酸。用FT-IR、MS及1H NMR对其结构进行表征。采用正交试验考察Diels-Alder反应的最佳反应条件为：桐油酸甲酯与马来酸酐投料比为1∶1.2，反应温度为160 ℃，反应时间为2 h。

关键词: 桐油, 马来酸酐, Diels-Alder反应, C22三元羧酸