Acetic Acid → 2-Bromo-4-(trifluoromethyl)benzoic acid

Temperature

-10 °C

205 g (1 mol) of 4-(trifluoromethyl)anthranilic acid, 600 ml of glacial acetic acid and 400 ml of 47% hydrobromic acid are introduced successively into a three-liter round-bottomed flask. After dissolution, the reaction mixture is cooled to -10° C., diluted with 400 ml of water and then treated dropwise with a solution of 69 g (1 mol) of sodium nitrite in 200 ml of water while maintaining the temperature below 0° C. When the addition is finished, the reaction mixture is stirred at 0° C. for 2 hours. This solution is run in dropwise into a six-liter reactor containing 143.5 g (1 mol) of cuprous bromide in 500 ml of 47% hydrobromic acid maintained at 60° C. When the addition is finished, the reaction mixture is stirred at 60° C. for one hour, cooled to room temperature and then poured into two liters of ice-cold water. The precipitate which forms is filtered on sintered glass, washed with water and then dried under a stream of air. There is thus obtained 216 g (yield: 80%) of 2-bromo-4-(trifluoromethyl)benzoic acid in the form of a solid melting at 118.5° C.

1. dissolutionAfter dissolution
2. temperaturewhile maintaining the temperature below 0° C
3. additionWhen the addition
4. temperaturemaintained at 60° C
5. additionWhen the addition
6. stirringthe reaction mixture is stirred at 60° C. for one hour
7. temperaturecooled to room temperature
8. filtrationThe precipitate which forms is filtered on sintered glass
9. washwashed with water
10. customdried under a stream of air

ORD record

ord-593f390d21b44bd0bfa3e3cbbd0b2b3d

Source dataset

uspto-grants-1996_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05514719