反应详情

20 g of diisopropyl malonate were initially charged in 173 g of toluene. Subsequently, 12 g of potassium tert-butoxide were added in portions at room temperature. After 2 hours, the solvent was removed under reduced pressure and admixed again with 173 g of toluene. At 0° C., 6 g of chloroacetyl chloride were added dropwise and the reaction mixture was then stirred at room temperature. Subsequently, 50 g of ice and 100 ml of water were added and the mixture was stirred for 10 minutes. The organic phase was removed and dried over magnesium sulphate. After the solvent had been removed, a 1:1 mixture of isopropyl 2-isopropoxy-4,5-dihydro-4-oxofuran-3-carboxylate (45% yield) and diisopropyl malonate was obtained. The mixture could be used thus in the next stage. With the aid of column chromatography, the isopropyl 2-isopropoxy-4,5-dihydro-4-oxofuran-3-carboxylate was isolated.

1. customthe solvent was removed under reduced pressure
2. additionAt 0° C., 6 g of chloroacetyl chloride were added dropwise
3. additionSubsequently, 50 g of ice and 100 ml of water were added
4. stirringthe mixture was stirred for 10 minutes
5. customThe organic phase was removed
6. dry with materialdried over magnesium sulphate
7. customAfter the solvent had been removed