Lithium Hydroxide → 2-(2-Fluoro-4-iodophenylamino)-1,5-dimethyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid

A 100 mL round-bottom flask was charged with methyl 2-(2-fluoro-4-iodophenylamino)-1,5-dimethyl-6-oxo-1,6-dihydropyridine-3-carboxylate (2.38 g, 6.72 mmol) and THF (80 mL). To the mixture was added LiOH (20 mmol) previously dissolved in 30 mL of H2O and the reaction was stirred at room temperature for 72 hours. The organic solvent was removed under reduced pressure and the resulting aqueous layer was acidified with 1N aq. HCl. The precipitate was filtered and dried under vacuum to afford the title compound as a white solid (2.12 g, 92%).