反应详情

温度

0 °C

To ethyl 4-bromo-2-methyl-3-oxopentanoate (7.49 g, 31.6 mmol) was added cold potassium hydroxide (4.7 g, 84 mmol) in water (36 mL) at 0° C., the resulting mixture was vigorously stirred at 0° C. for 4 h. The reaction mixture was extracted with methylene chloride (2×100 mL), the alkaline phase was acidified to ph 1 by 6N hydrogen chloride followed by extraction with methylene chloride (3 times 100 mL). The combined latter organic phase was dried over sodium sulfate, and concentrated to give 4-hydroxy-3,5-dimethylfuran-2(5H)-one. LCMS: (M+23)+: 151.10, 1HNMR (500 MHz, CDCl3), δ4.882-4.842 (dd, J=6.8 Hz, 1H), 3.744 (s, 1H), 1.759(s, 3H). 1.526-1.513 (d, J=6.8 Hz, 3H).

1. extractionThe reaction mixture was extracted with methylene chloride (2×100 mL)
2. extractionfollowed by extraction with methylene chloride (3 times 100 mL)
3. dry with materialThe combined latter organic phase was dried over sodium sulfate
4. concentrationconcentrated