2-Bromo-4-fluorobenzoic acid (2.37 g, 10.82 mmol) was dissolved in anhydrous ethanol (100 mL). Thionyl chloride (1.57 mL, 21.64 mmol) was slowly added under stirring, followed by heating the reaction mixture to reflux temperature and continuous stirring for 24 hours. Upon completion of the reaction, the reaction system was cooled to room temperature. Most of the solvent was removed by distillation under reduced pressure. The residue was washed with water and subsequently extracted with ethyl acetate (3 × 50 mL). The organic phases were combined, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. Finally, the crude product was purified by silica gel column chromatography to afford ethyl 2-bromo-4-fluorobenzoate (2.29 g, 87% yield) as a colorless liquid.
