Step 1: Synthesis of methyl 2-bromo-6-fluorobenzoate (2). 2-Bromo-6-fluorobenzoic acid (1, 12.50 g, 57 mmol) was dissolved in a mixture of methanol (60 mL) and concentrated sulfuric acid (65 mL). The reaction mixture was heated to 80 °C and stirred at this temperature for 12 hours. Upon completion of the reaction, the mixture was cooled to room temperature and the pH was adjusted slowly by adding 20% sodium carbonate solution (500 mL) to 8. Subsequently, extraction was carried out with dichloromethane (3 x 180 mL), the organic phases were combined and dried with anhydrous magnesium sulfate. Finally, the solvent was evaporated under reduced pressure to afford the title compound methyl 2-bromo-6-fluorobenzoate (11.29 g, 48.5 mmol, 85% yield) as a brown oil.
