Water → 3-Bromo-2-chloro-4,5-difluorobenzoic acid
Reaction equation
[Br:1][C:2]1[C:3]([Cl:12])=[C:4]([CH:7]=[C:8]([F:11])[C:9]=1[F:10])[C:5]#N.[OH2:13].S(=O)(=O)(O)[OH:15]>>[Br:1][C:2]1[C:3]([Cl:12])=[C:4]([CH:7]=[C:8]([F:11])[C:9]=1[F:10])[C:5]([OH:15])=[O:13]Participants
4
Conditions
- Temperature
- 100 °C
Procedure
A solution of 3-bromo-2-chloro-4,5-difluorobenzonitrile (9.8 g) in concentrated sulfuric acid (10 ml) was stirred at 100° C. for 35 minutes. After cooling, 18N sulfuric acid (50 ml) and water (10 ml) were added to the reaction mixture. The reaction mixture was stirred at 100° C. for 4 hours and then poured into ice water (300 ml). The resulting precipitate was collected by filtration, washed with water sufficiently and recrystallized from dichloromethane-n-hexane to give the title compound (9.24 g) as colorless prisms, mp 137.5°-139.5 ° C.