【作者】 胡日东；

【导师】 李春萍；

【作者基本信息】 内蒙古工业大学 ， 化学工程， 2009， 硕士

【摘要】 实验研究了2,6-二羟基苯甲酸(2,6-DHBA)的合成。2,6-DHBA是一种重要的有机合成中间体,广泛地应用于医药、染料、农药等领域,如可以合成嘧啶水杨酸、双嘧草醚以及新型高效除草剂KIH-2023,因此对其制备方法的研究具有重要的意义。实验中,以间苯二酚和碳酸钾为原料,于有机溶剂中,通入CO2气体,在170℃及常压条件下经Kolbe-Schmitt羧基化反应得到产品2,6-DHBA。实验结果表明,在一般条件下,活泼的酚盐-间苯二酚钾与弱的亲电试剂-二氧化碳能发生亲电取代反应,生成相应的芳羟基羧酸,得动力学控制产物2,6-DHBA。实验对2,6-DHBA的合成工艺进行了探索,详细讨论了反应温度、有机溶剂、反应物的摩尔配比等对2,6-DHBA收率和质量的影响。为了提高2,6-DHBA的收率,实验采用了新的溶剂二乙二醇,使反应能在较温和的条件下进行,最重要的是将压力由高压条件转变为常压。通过正交试验得到最佳反应条件为:反应温度170℃,反应时间6小时左右,间苯二酚和碳酸钾物质的量的比例为1:0.5。2,6-DHBA的收率超过35%。通过熔点测试、IR、XRD对产品进行了表征,确定实验所得产品就是2,6-DHBA。更多还原

【Abstract】 The synthesis of 2,6-Dihydroxybenzoic acid(2,6-DHBA) has been investigated. 2,6-DHBA is an important organic synthetic intermediate,which is widely used in the production of pharmaceutical, colorants and pesticide and so on. For instance , it can be used to synthesize bispyribac-sodium acid Bispyribac-sodium and highly efficient herbicide KIH-2023. Beginning from the raw material-resorcinol, carboxylation reaction with carbon dioxide gas in the presence of potassium carbonate was proceeded at 170℃and atmospheric pressure, then the main product was 2,6-DHBA. The experiments have proved that the products controlled by dynamics are obtained under ordinary conditions. The synthesis conditions of 2,6-DHBA were optimized on the base of experiments. The effect of reaction temperature and organic solvent and ratio of raw material and quality of the product was discussed in detail. In order to increase the yield, a new solvent diglycol is used in this experiment, because of its existence, carboxylation reaction may proceed under temperate condition, most importantly it causes the pressure to become the atmospheric pressure. By orthogonal test, the best conditions for preparation of 2,6-DHBA were as follows: reaction time is 6h; reaction temperature 170℃.the molar ratio of resorcinol to Potassium carbonate 1:0.5.The yield of 2,6-DHBA is more than 35%. Then its typical structure characteristics are taken with IR,melting point and XRD.更多还原