水杨酸苄酯的绿色合成

Green synthesis of benzyl salicylate

采用水杨酸钠和氯化苄为原料,以N,N-二甲基甲酰胺为溶剂,无相转移催化剂条件下,加热均相反应合成水杨酸苄酯,测定所合成的水杨酸苄酯的红外光谱和折射率并与文献报道值比较,从而确认水杨酸苄酯的结构。考察了反应温度、反应物配比、反应时间等对酯化反应收率的影响。确定了反应的最佳条件为:n(水杨酸钠)∶n(氯化苄)=2.5∶1,反应温度100℃,反应时间2.5h,此条件下水杨酸苄酯的收率达98.4%。与现有的水杨酸苄酯合成方法相比,该方法收率高,副产物少,反应时间短,分离方便,溶剂可以回收重复使用,绿色环保,适合于工业化生产。

Benzyl salicylate was synthesized by homogeneous reaction of sodium salicylate with benzyl chloride in dimethyl formamide solvent under heating and phase transfer catalyst - free conditions. The structure of benzyl salicylate was confirmed by measuring IR spectrum and refractive index and comparing with that reported in literature. The effects of reaction temperature, mole ratio of reactants and reaction time on the esterification yield were also investigated. The optimized reaction conditions were obtained as follows： the male ratio of sodium salicylate to benzyl chloride was 2. 5 ： 1, the reaction temperature was 100℃, and reaction time was 2. 5 h. Under the optimal reaction conditions, the yield of benzyl salicylate can reach 98.4%. Compared with the existing synthesis of benzyl salicyate, this green synthetic procedure has the advantage of high yield and less side - product, short reaction time, convenient separation, easy recovery and reusability of the solvent and suitability for industrialization.