反应详情

3-Amino-2,6-dichloroisonicotinic acid methyl ester (460 mg) was dissolved in ethanol (8 mL), water (2 mL) and potassium hydroxide (234 mg) was added. The solution was stirred for 20 minutes at room temperature and for 1.5 hours under reflux. After cooling to room temperature, 2N hydrochloric acid was added to adjust the pH-value to −3 and the so-formed yellow precipitate was extracted 3× with ethyl acetate. The combined organic layer was washed with brine, dried over MgSO4 and concentrated in vacuum to afford 420 mg of the title compound of the formula

1. temperatureunder reflux
2. temperatureAfter cooling to room temperature
3. extractionthe so-formed yellow precipitate was extracted 3× with ethyl acetate
4. washThe combined organic layer was washed with brine
5. dry with materialdried over MgSO4
6. concentrationconcentrated in vacuum