TFA (5 mL) was added to a solution of (2- chloro-3-fluoropyridin-4-yl)carbamic acid fert-butyl ester (1.9 g, 7.7 mmol) in DCM (10 mL). The solution was stirred at ambient temperature for 5 hours and concentrated under reduced pressure. The resultant residue was dissolved in DCM and purified by column chromatography on an NH2 cartridge (0-10 per cent MeOH in DCM) to afford 2-chloro-3-fluoropyridin-4-aMine as a beige solid (0.96 g, 94 per cent yield). NMR (400 MHz, CDC13): δ 7.82 (d, J = 5.4 Hz, 1H), 6.60 (t, J= 5.8 Hz, 1H), 4.38 (br s, 2H).
