异亚丙基甘油月桂酸酯脱保护反应条件的响应面优化

Optimization of the Deprotection Reaction Conditions of Isopropylidene Glyceryl Laurate by Using the Response Surface Methodology

单脂肪酸甘油酯是制备高值皮革加脂剂、人造革生物基增塑剂的关键中间体,但传统合成方法所得产物为单、多脂肪酸甘油酯混合物,前者含量一般不超过50%,且分离提纯困难。利用双羟基保护法可直接合成高纯单脂肪酸甘油酯,但最关键的脱保护反应条件难以控制。鉴于此,以月桂酸为代表,利用双羟基保护法合成异亚丙基甘油月桂酸酯,并借助响应面法对其脱保护反应条件进行优化。理论预测与真实实验结果较为契合,证实异亚丙基甘油月桂酸酯的最佳脱保护反应条件为:水与异亚丙基甘油月桂酸酯物质的量比3.4,反应温度44℃,反应时间5 h,催化剂浓盐酸用量0.9%;此条件下,单月桂酸甘油酯产物纯度可达95.5%。该研究工作为后续开发各类单脂肪酸甘油酯基高值皮化材料奠定了基础。

Monoglyceride is a crucial intermediate for preparing high-value fatliquors for leather and bio-plasticizers for PVC synthetic leather.However,the products obtained by using the traditional synthesis method are the mixture of mono-,di-and tri-glycerides,in which the content of monoglycerides is generally lower than 50%.Meanwhile,extracting the monoglycerides from the mixture is also a challenge.The high-purity monoglycerides can be directly synthesized by using the dihydroxyl protection method,but the deprotection reaction condition,which is the most crucial for the purity of the final products,is difficult to control.Here,using lauric acid as a representative,isopropylidene glyceryl laurate was synthesized by using the dihydroxyl protection method,and the deprotection reaction conditions were optimized by using the response surface methodology.The theoretical prediction fitted well with the experimental results.It was demonstrated that the purity of glycerol monolaurate prepared by using the dihydroxy protection method could reach 95.5%under the optimal deprotection reaction conditions,i.e.,3.4 molar ratio of water to isopropyl glycerol laurate,reaction temperature of 44℃,reaction time of 5 h,and the hydrochloric acid concentration of 0.9%.The present effort may lay the foundation for leather industry to prepare monoglyceride-based high-value leather chemicals.