2-Fluoropyridine-6-carboxylic acid

407-22-7

402-69-7

General procedure for the synthesis of 6-fluoro-2-pyridinecarboxylic acid from 2-fluoro-6-methylpyridine: to a solution of 2-fluoro-6-methylpyridine (2.5 g, 22.5 mmol) in water (170 ml) was added potassium permanganate (KMnO, 2 g, 12.65 mmol) in batches and the mixture was heated to reflux. Subsequently, potassium permanganate (KMnO, 8 g, 50.63 mmol) was added in batches and heating to reflux was continued for 3 hours. After completion of the reaction, the mixture was cooled and the precipitate was removed by filtration. The filtrate was acidified with hydrochloric acid (HCl) solution and subsequently concentrated under reduced pressure. The residue was ground with hot ethanol (EtOH), the solid was collected by filtration and the filtrate was concentrated to dryness under reduced pressure. 6-Fluoro-2-pyridinecarboxylic acid was finally obtained as a white solid (1.7 g, 53% yield); melting point 137 °C.