反应详情

温度

0 °C

[step 1] Methyl 2-(2-methoxyacetamido)benzoate (U.S. Pat. No. 5,091,403; 3.0 g, 13.4 mmol) was suspended in butyric anhydride (12.7 mL, 134.0 mmol), fuming nitric acid (2.3 mL, 51.1 mmol) was added dropwise under ice-cooling, and the mixture was stirred at 0° C. for 40 min. Water was added to the mixture, 4 mol/L aqueous sodium hydroxide solution was added dropwise to neutralize the mixture, and the mixture was extracted 3 times with ethyl acetate. The combined organic layers were dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=100/0 v/v-60/40 v/v) to give methyl 2-(2-methoxyacetamido)-3-nitrobenzoate (1.9 g, 51%).

1. temperaturecooling
2. additionwas added dropwise
3. extractionthe mixture was extracted 3 times with ethyl acetate
4. dry with materialThe combined organic layers were dried over anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate=100/0 v/v-60/40 v/v)