反应详情

To a solution of diethyl malonate (8.01 g; 50 mmol) in dry DMF (25 mL) under nitrogen atmosphere was added potassium carbonate (7.6 g; 55 mmol), which has been dried at 120° C. for 12 h before using. After stirring for 15 min at room temperature, ethyl 2-bromovalerate (8.53 mL; 50 mmol) was slowly added under nitrogen and the mixture was vigorously stirred at room temperature for 24 h. The reaction mixture was poured in water (240 mL) and neutralized by adding a solution of hydrochloric acid 6N. The product was extracted with diethyl ether (2x240 mL) and the combined organic layers were dried over magnesium sulphate, filtered and concentrated under reduced pressure. Purification by distillation under reduced pressure furnished 12.8 g (99%) of the title compound as a colorless liquid (bp. 117° C., 2 mbar, temperature of the oil bath 165° C.).

1. customhas been dried at 120° C. for 12 h
2. stirringthe mixture was vigorously stirred at room temperature for 24 h
3. extractionThe product was extracted with diethyl ether (2x240 mL)
4. dry with materialthe combined organic layers were dried over magnesium sulphate
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customPurification
8. distillationby distillation under reduced pressure