2-(2-甲氧基乙氧基)乙醛二乙醇缩醛的合成工艺研究

Synthesis of 2-(2-Methoxyethoxy)acetaldehyde Diethyl Acetal

将金属钠溶解于乙二醇单甲醚生成钠盐后立即与溴代乙醛二乙醇缩醛反应，合成了半合成大环内酯类抗生素的重要中间体２（２甲氧基乙氧基） 乙醛二乙醇缩醛，避免了旧有工艺需使用价格昂贵且危险性较高的原料氢化钠的缺点。采用正交实验法得到最佳反应条件：金属钠与溴代乙醛二乙醇缩醛的物质的量比为１∶１－５，溶剂的量为０－３６ ｍＬ／ｍｍｏｌ，反应时间为１０ ｈ，产物的收率为９１－７ ％ 。新工艺易于控制，成本较低，适于工业生产。

Methoxyethoxy)acetaldehyde diethyl acetal, an important intermediate for the semi synthesis of macrolide antibiotics, was prepared by dissolving metallic sodium in methoxyethanol and immediately condensing with bromoacetaldehyde diethyl acetal. The drawback of the old method to use the expensive and dangerous material sodium hydride was avoided. The optimum reaction conditions were obtained by orthogonal test:molar ratio of metallic sodium to bromoacetaldehyde diethyl acetal was 1∶1 5, amount of solvent 0 36mL/mmol, reaction time 10h. The yield was 91 7%. The reaction was easier to control and the cost was lower. This new method is more suitable for the industrial production.