反应详情

The above ester (2.20 g) was added to 1 N sodium hydroxide solution (20 ml), and the mixture was refluxed for 30 minutes, then poured into ice-water, made acidic with concentrated hydrochloric acid and extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate and evaporated. The resulting residue was purified by silica gel column chromatography, eluting with dichloromethane-methanol (10:1), and recrystallized from n-hexane-ethyl acetate to give the title compound (1.60 g, 77.1 %) as colorless crystals, mp 108-110° C.

1. temperaturethe mixture was refluxed for 30 minutes
2. extractionextracted with ethyl acetate
3. washThe organic layer was washed with water
4. dry with materialdried over anhydrous sodium sulfate
5. customevaporated
6. customThe resulting residue was purified by silica gel column chromatography
7. washeluting with dichloromethane-methanol (10:1)
8. customrecrystallized from n-hexane-ethyl acetate