Hydrogen Bromide → 4-Bromo-2-fluoro-3-methylbenzoic acid

Participants

Reaction Steps

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.

Provenance & Evidence