2-Amino-5-chloro-3-fluoropyridine

89402-43-7

246847-98-3

General procedure for the synthesis of 2-amino-3-fluoro-5-chloropyridine from 2,3-difluoro-5-chloropyridine: 5-chloro-2,3-difluoropyridine (100 g, 0.669 mol) and liquid ammonia (1.125 L, 8.025 mol) were placed in an autoclave. The kettle was sealed and the reaction was carried out at 120 °C for 24 hours. Upon completion of the reaction, the reaction mixture was cooled and formation of a yellowish solid precipitate was observed. The precipitate was separated by filtration and the filter cake was washed with deionized water. The filtrate was extracted with ethyl acetate, the organic layers were combined and dried with anhydrous sodium sulfate. Subsequently, the organic solvent was removed by distillation under reduced pressure, and a small amount of petroleum ether was added to the residue, which was filtered again to obtain a precipitate of the target compound 2-amino-3-fluoro-5-chloropyridine. The final product was obtained as 84.22 g in 85.94% yield.