碘催化的葡萄糖异亚丙基缩酮反应研究

Iodine-Catalyzed Reaction of D-Glucose with Aceton for the Preparation of 1,2-5,6-di-O-Isopropylidene-alpha -D-glucofuranose (DAG)

以无水葡萄糖为原料、碘为催化剂,催化无水葡萄糖与丙酮的异亚丙基缩酮反应,形成1,2-5,6-双-氧-异丙叉-α-D-呋喃葡萄糖(1,2-5,6-di-O-isopropylidene-α-D-glucofuranose,diacetone glucose,DAG),并对反应条件进行初步研究。结果表明:碘做催化剂,在回流条件下,5h能催化葡萄糖与丙酮生成产物DAG;而在低于回流温度反应时,反应时间明显变长。在反应物料最佳物质的量比为葡萄糖:碘:丙酮=1:0.15:122.5时,最高收率为75%左右;4A分子筛的加入并不能显著提高反应收率。

1,2-5,6-di-O-Isopropylidene-a-D-glucofuranose （DAG）, a glucose derivative, was obtained by the reaction of D- glucose with acetone. Effects of various conditions such as temperature, D-glucose/iodine/acetone ratio （molar） and amount of added 4A molecular sieve on production yield of DAG were investigated. In the presence of iodine, heating for 5 h under reflux （at 62 ℃ ） allowed the generation of DAG from the reaction between D-glucose and acetone. However, the reaction time was greatly extended when the reaction temperature was below 62℃. At optimized D-glucose/iodine/acetone ratio of 1：0.15：122.5, the yield of DAG was found to be close to 75%. No obvious effect was found on the yield of DAG with the addition of 4A molecular sieve.