反应详情

温度

100 °C

The procedure described in R. K. Bentley and F. G. Holliman, J. Chem. Soc. (c), 2447 (1970) was used. A mixture of 2,5-dibromobenzoic acid (50 g, 0.18 mol) in concentrated sulfuric acid was vigorously stirred as fuming nitric acid (62.5 mL) was added dropwise at a rate to keep the temperature below 70° C. The reaction mixture was vigorously stirred, heated to 100° C. and then kept at 100° C. for 5 hours. The cooled reaction was cautiously poured into 2 liters of ice and vigorously stirred, the precipitate was filtered through a sintered glass funnel and the solid was washed well with water. Crystallization was achieved by dissolving the solid in acetic acid (150 mL) and after concentration to a half of the volume, crystals separated (16.72 g) ; mp 225°-229° C. An additional crop of 7.52 g was obtained to give a total yield of 24.24 g (41%).

1. additionwas added dropwise at a rate
2. customthe temperature below 70° C
3. customThe cooled reaction
4. stirringvigorously stirred
5. filtrationthe precipitate was filtered through a sintered glass funnel
6. washthe solid was washed well with water
7. customCrystallization
8. dissolutionby dissolving the solid in acetic acid (150 mL)
9. concentrationafter concentration to a half of the volume, crystals
10. customseparated (16.72 g)
11. customAn additional crop of 7.52 g was obtained
12. customto give a total yield of 24.24 g (41%)