反应详情

Methyl 2-chloro-3-oxo-pentanoate obtained in Example (22a) (1.91 g, 11.57 mmol) was dissolved in ethanol (50 mL). Thiourea (0.77 g, 10.09 mmol) was added, and the mixture was heated under reflux for 1.5 hours. The reaction solution was concentrated under reduced pressure, diluted with ethyl acetate, washed with saturated aqueous sodium bicarbonate solution and brine, and dried over anhydrous sodium sulfate. Following concentration under reduced pressure, the residue was washed with hexane/ethyl acetate: 5/1 to obtain 1.78 g of the title compound as a pale yellow solid (95%).

1. temperaturethe mixture was heated
2. temperatureunder reflux for 1.5 hours
3. concentrationThe reaction solution was concentrated under reduced pressure
4. additiondiluted with ethyl acetate
5. washwashed with saturated aqueous sodium bicarbonate solution and brine
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationconcentration under reduced pressure
8. washthe residue was washed with hexane/ethyl acetate