Sodium percarbonate → 3,4-Difluorobenzoic acid
Reaction equation
[C:1]([O-:4])([O-])=[O:2].C([O-])([O-])=O.OO.OO.OO.[Na+].[Na+].[Na+].[Na+].[F:19][C:20]1[CH:21]=[C:22]([CH:31]=[CH:32][C:33]=1[F:34])C(C1C=CC=CC=1)=O>FC(F)(F)C(O)=O>[F:19][C:20]1[CH:21]=[C:22]([CH:31]=[CH:32][C:33]=1[F:34])[C:1]([OH:4])=[O:2]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
2.5 g of sodium percarbonate were added over 1 h to a solution of 2.2 g (10 mmol) of 3,4-difluorobenzophenone and 20 ml of trifluoroacetic acid (0° C.) and the temperature was then allowed to rise to 20° C. The mixture was stirred for 16 h at this temperature and 50 g of ice were then added. The mixture was subsequently extracted twice with dichloromethane and the organic phases were washed (NaHCO3) until the washings were neutral. The solvent was then removed. Working-up as described in Example 22 gave 1.2 g (7.6 mmol, 76%) of 3,4-difluorobenzoic acid, which can be obtained analytically pure from water (melting point 113°-120.5° C.).