A solution of 2-fluoro-3-nitrobenzoic acid (5 g, 27.0 mmol) in MeOH (50 mL) was treated with concentrated H2SO4 (1.4 mL, 27.0 mmol) and the resulting reaction was stirred at 50 °C for 16 h. The solvent was removed under reduced pressure and the residue was diluted with EtO Ac. The organic solution was washed with saturated aqueous NaHCO3 solution until the water phase reached neutral pH. The two phases were separated. Organics were washed with water, brine and dried (Na2SO4). The solution was filtered and concentrated to give crude methyl 2-fluoro-3-nitrobenzoate which was used as is in the next step. (5.1 g, 25.2 mmol, 93 %) as a pale yellow solid.
