o,o-EDDHA的制备、表征及反应条件优化

Preparation,Characterization and Optimization of Reaction Conditions

以苯酚、乙醛酸和乙二胺等为原料,通过曼尼希反应一步得到乙二胺二邻羟苯基乙酸(o,o-EDDHA),通过FT-IR、1H NMR对其进行了表征。研究了反应温度、反应时间、配料比、原料浓度、相转移催化剂种类等对o,o-EDDHA收率和选择性的影响。研究结果表明EDDHA的优化合成条件为:反应温度55℃,反应时间为3 h,配料比为苯酚∶乙醛酸∶乙二胺∶氢氧化钠=2.6∶2∶1∶0.1(摩尔比),乙醛酸的浓度为20%,相转移催化剂为四丁基氢氧化铵,目标产物o,o-EDDHA的最高收率可达到69.7%,选择性达97%,与相关文献报道中的收率和选择性相比具有很大提高。

Ethylenediamine N,N＇-bis（2-hydroxyphenyl）acetic acid （o,o-EDDHA） was synthesized through Mannich reaction using phenol, glyoxylic acid and ethylenediamine. The structure of o,o-EDDHA was confirmed by FT-IR and 1H NMR. The synthesis conditions of this reaction such as temperature, time, ratio, the concentration of the material and phase transfer catalyst were investigated. The optimizing conditions are as follows： reaction temperature is 55 ~C, reaction time is 3 h, the molar ratio of phenol, glyoxylic acid, ethylenediamine and sodium hydroxide is 2.6 ： 2 ： 1 ; 0.1, the concentration of glyoxylic acid is 20 %, the phase transfer catalyst is tetrabutylammonium hydroxide, the highest yield of o,o-EDDHA is 69.7 %, the selectivity is 97 %.