反应详情

温度

64 °C

To a 500 mL round-bottom flask, 0.2 mol of 2-amino-3,5-dichlorobenzoic acid having a structural formula of IV-4, 300 mL of methanol, and 5 mL of concentrated sulfuric acid were added, heated to 64° C. and reacted for 12 hours (into which 3 mL of concentrated sulfuric acid was added twice), after cooling most of the solvent was removed under reduced pressure, and 300 mL of water was added, the pH was adjusted to 9-10 with a saturated sodium hydroxide solution, extracted with 200 mL of ethyl acetate, washed with water for one time, dried over anhydrous sodium sulfate, filtered and the solvent was remove to obtain a crude product, 34.6 grams of 2-amino-3,5-dichlorobenzoic acid methyl ester having a structure as shown by VIII-1 was obtained by column chromatography, and the yield was 78.6%;

1. additionwas added twice),
2. temperatureafter cooling most of the solvent
3. customwas removed under reduced pressure, and 300 mL of water
4. additionwas added
5. extractionextracted with 200 mL of ethyl acetate
6. washwashed with water for one time
7. dry with materialdried over anhydrous sodium sulfate
8. filtrationfiltered
9. customthe solvent was remove