反应详情

温度

60 °C

To a stirred solution of 2,5-difluorobenzoic acid (20 g, 126 mmol) in MeOH (250 mL) is added thionyl chloride (22.5 g, 190 mmol) dropwise at ice-cold conditions. After complete addition the reaction mixture is heated at 60° C. for 3 h. The reaction mixture is concentrated and the residue neutralized with aqueous Na2CO3 solution. It is extracted with CH2Cl2 (3×100 mL), dried over anhydrous MgSO4 and concentrated under reduced pressure to afford the desired 2,5-difluorobenzoic acid methyl ester as a thick liquid (22 g).

1. additionAfter complete addition the reaction mixture
2. concentrationThe reaction mixture is concentrated
3. extractionIt is extracted with CH2Cl2 (3×100 mL)
4. dry with materialdried over anhydrous MgSO4
5. concentrationconcentrated under reduced pressure