甲基格氏试剂甲基硫酸甲基镁的合成

Synthesis of Methylmagnesium Methylsulphate as Methyl Grignard Reagent

250ml四口烧瓶中加入镁粉2.4g(0.1mol),碘0.04g,充氮置换,搅拌下慢慢升温至40℃,保温20min。加入碘甲烷0.5g和四氢呋喃10g混合液,冷水浴控温40℃左右,搅拌,直至反应液呈乳白色。冷却至10℃左右,于30min内,将硫酸二甲酯14.3g(0.11mol)和四氢呋喃50ml混合液自滴液漏斗中慢慢地匀速滴入,滴毕继续保温搅拌10min以使镁粉转化完全,得灰黑色甲基硫酸甲基镁溶液,Zerevitinnov活泼氢测定法显示活性甲基收率≥90%(以镁计),所得溶液可替代传统的甲基格氏试剂甲基卤化镁,不经分离可直接用于有机合成。

A250ml.four-necks roud-bottomed flask which is charged with nitrogen,is covered with 2.4g.of magnesium powder （0.1mol） and 0.04g. of iodine.Then the reactant is brought slowly to about 40℃.and maintained forthe flask,the mixture is stirred at about 40℃.to milky whiteahydrofuran is added slowly and equally from a dropping funnel while the temperature is maintaineconvertion of magnesium complete.The solution of methylmagnesium methylsulphate obtained appears grey-dark. Zerevitinnov reactive hydrogen measuring method indicates yield of the activity methyl more than 90%,base on magnesium.This solution can be used without separation in organic synthesis instead of conventional methyl Grignard reagent methylmagnesium halide.