反应详情

温度

0 °C

To a 0° C. suspension of NaH (60% in mineral oil, 658 mg, 16.5 mmol) in THF (20 mL) under nitrogen was slowly added a solution of imidazole (1.03 g, 15.1 mmol) in THF (20 mL). The resulting suspension was stirred at 0° C. for 15 minutes, then ethyl bromoacetate (2.2 mL, 20 mmol) was added. The reaction was stirred at room temperature for 4.5 hours, then was diluted with H2O (25 mL). The THF was evaporated under reduced pressure and the remaining aqueous solution was extracted with CH2Cl2 (25 mL×3). The combined organic solution was dried (Na2SO4), filtered and concentrated under reduced pressure. Purification by flash column chromatography on silica (CH2Cl2/MeOH, 19:1) gave the ester as a yellow liquid (1.52 g, 9.87 mmol, 65%). 1H NMR (CDCl3) δ 1.28 (t, 3H, J=7.1 Hz), 4.24 (q, 2H, J=7.1 Hz), 4.68 (s, 2H), 6.95 (s, 1H), 7.09 (s, 1H), 7.50 (s, 1H).

1. stirringThe reaction was stirred at room temperature for 4.5 hours
2. customThe THF was evaporated under reduced pressure
3. extractionthe remaining aqueous solution was extracted with CH2Cl2 (25 mL×3)
4. dry with materialThe combined organic solution was dried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customPurification by flash column chromatography on silica (CH2Cl2/MeOH, 19:1)