一种合成三氯蔗糖-6-乙酯的新方法

以蔗糖为原料，采用单基团保护法合成蔗糖-6-乙酯；采用固体光气与DMF合成Vilsmeier试剂，氯化蔗糖-6-乙酯过程中不污染环境。经IR、1H NMR确认三氯蔗糖-6-乙酯结构。考察了投料比、缚酸剂及升温时间等条件对产物收率的影响。结果表明，二次乙酰化反应较佳条件为：m(水)∶m(原乙酸三甲酯)∶m(对甲苯磺酸)= 10.0∶3.5∶0.06；氯化反应较佳条件为：n(固体光气)∶n(蔗糖-6-乙酯) =5∶1，以吡啶为缚酸剂，分3个阶段升温，2 h升温到70 ℃、2 h升温到90 ℃、3 h升温到110℃最适宜进行氯代反应，总收率为57.3%。

A new method of synthesis of sucralose-6-acetate

Sucrose-6-acetate was synthesized from sucrose through monogroup protection. Vilsmeier reagent was prepared from triphosgene and DMF. The process to chlorinate sucrose-6-acetate with Vilsmeier reagent for sucralose-6-acetate would not bring about pollution. Structure of sucralose-6-acetate was confirmed by IR, 1H NMR. In this study, the effects of molar ratio of raw materials, heating time and the kind of acid scavengers on the yield were investigated. The results indicated that the optimum condition of second acetalization reaction was mass ratio of water, trimethyl orthoacetate and p-toluenesulfonic acid 10.0∶3.5∶0.06. The optimum condition of chlorination was molar ration of triphosgene and sucrose-6-ethyl 5∶1. Heating temperature was divided into 3 steps，70 ℃ in 2hrs，90 ℃ in 2 hrs and 110 ℃ in 3 hrs, which was in favor of the chlorination with pyridine as acid scavengers. The yield was 57.3% under above condition.