反应详情

To the compound (4.80 g, 12.6 mmol) obtained in Example 1c were added ethanol (40 mL), tetrahydrofuran (10 mL) and 2N aqueous sodium hydroxide solution (12.6 mL, 25.2 mmol), and the mixture was stirred overnight. The reaction mixture was concentrated under reduced pressure, and the residue was extracted with water, and washed with ether. The aqueous layer was acidified with 6N hydrochloric acid, extracted with ethyl acetate, washed with saturated brine, dried over sodium sulfate, and concentrated under reduced pressure. The residue was recrystallized from ethyl acetate-hexane to give the title compound (3.0 g, 67%) as colorless crystals.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. extractionthe residue was extracted with water
3. washwashed with ether
4. extractionextracted with ethyl acetate
5. washwashed with saturated brine
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe residue was recrystallized from ethyl acetate-hexane