反应详情

A total of 21.6 g of isobutylmalonic acid diethyl ester prepared above was dissolved in 100 ml of ethanol and treated dropwise at 0° with a solution of 5.6 g of potassium hydroxide in 100 ml of ethanol. The solution was allowed to stand to neutral pH for 17 hours at 20° and then evaporated under reduced pressure. The residue was dissolved in ice-water and extracted three times with ethyl acetate. The ethyl acetate extracts were rejected. The aqueous phase was acidified with 2-N hydrochloric acid and extracted twice with ethyl acetate. The combined ethyl acetate extracts were washed once with water, dried over magnesium sulfate and evaporated under reduced pressure. There were obtained 15.3 g of colorless isobutylmalonic acid monoethyl ester in the form of a chromatographically pure oil.

1. customevaporated under reduced pressure
2. dissolutionThe residue was dissolved in ice-water
3. extractionextracted three times with ethyl acetate
4. extractionextracted twice with ethyl acetate
5. washThe combined ethyl acetate extracts were washed once with water
6. dry with materialdried over magnesium sulfate
7. customevaporated under reduced pressure