Reaction #302897

Reaction equation

sulfuric acid

2-fluoro-3-methylthio-4-(trifluoromethyl)benzoic acid

methanol

→

methyl 2-fluoro-3-methylthio-4-(trifluoromethyl)benzoate

Conditions

Workup

1. 1
   Temperaturethe mixture was heated
2. 2
   Temperatureunder reflux until HPLC analysis
3. 3
   TemperatureThe mixture was cooled
4. 4
   Otherthe solvent was removed
5. 5
   Extractionthe mixture was extracted twice with ethyl acetate
6. 6
   WashThe combined organic phases were washed once with saturated aqueous NaHCO3 solution
7. 7
   OtherFinally, the organic phase was dried
8. 8
   Concentrationthe filtrate was concentrated

Procedure

5 ml of concentrated sulfuric acid were added to 20.0 g (78.7 mmol) of 2-fluoro-3-methylthio-4-(trifluoromethyl)benzoic acid in 200 ml of methanol, and the mixture was heated under reflux until HPLC analysis showed complete conversion. The mixture was cooled and the solvent was removed. The residue was taken up in water, and the mixture was extracted twice with ethyl acetate. The combined organic phases were washed once with saturated aqueous NaHCO3 solution. Finally, the organic phase was dried and the filtrate was concentrated. This gave 20.5 g of methyl 2-fluoro-3-methylthio-4-(trifluoromethyl)benzoate.

Source