反应详情

Methylamine (13.5 mL, 40% in water) is added to an ice-cooled mixture of 2,4-difluoro-5-nitro-benzoic acid (10.0 g, 49 mmol) in water (100 mL) and it is stirred for 30 min at rt. The mixture is acidified with 6N aq HCl-solution and the precipitate is filtered, washed with water and dried at 60° C. The crude material is recrystallized from MeOH. The final product is slightly contaminated by its regioisomer 4-fluoro-2-methylamino-5-nitro-benzoic acid.

1. temperaturecooled
2. filtrationthe precipitate is filtered
3. washwashed with water
4. customdried at 60° C
5. customThe crude material is recrystallized from MeOH