反应详情

In 14 ml of 4.7% hydrobromic acid was suspended 0.55 g of 4-amino-2-fluoro-3-methylbenzoic acid, and 3.7 g of cupric bromide was added thereto. To the resulting suspension was added dropwise a solution of 0.38 g of sodium nitrite in 4 ml of water under ice-cooling over a period of 15 minutes, and the resulting mixture was stirred at the same temperature for 1 hour and then at room temperature for 24 hours. To the reaction mixture was added 20 ml of toluene and the organic layer was separated. The organic layer obtained was washed with 20 ml of 20% hydrobromic acid, dried over anhydrous magnesium sulfate, and then distilled under reduced pressure to remove the solvent. n-Hexane was added to the resulting residue and the crystals were collected by filtration to obtain 0.68 g of colorless 4-bromo-2-fluoro-3-methylbenzoic acid.

1. additionwas added
2. temperaturecooling over a period of 15 minutes
3. waitat room temperature for 24 hours
4. customthe organic layer was separated
5. customThe organic layer obtained
6. washwas washed with 20 ml of 20% hydrobromic acid
7. dry with materialdried over anhydrous magnesium sulfate
8. distillationdistilled under reduced pressure
9. customto remove the solvent
10. additionn-Hexane was added to the resulting residue
11. filtrationthe crystals were collected by filtration