Ammonia → 4-Fluoro-3-(pyridin-2-yl)aniline

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Reaction Steps

To 2-(2-fluoro-5-nitrophenyl)pyridine (2.11 g, 9.68 mmol) in ethanol (40 ml), stirred in a water bath at 20° C., was added dry tin(II) chloride (7.10 g, 37.3 mmol) portionwise. The mixture was then stirred at room temperature for 18 h. Aqueous ammonia (40 ml of a 25% solution) was added, and the solvent was removed in vacuo, azeotroping with ethanol to remove traces of water. The residue was sequentially boiled in ethyl acetate and filtered three times. The combined filtrates were concentrated in vacuo to yield 4-fluoro-3-(pyridin-2-yl)aniline as a yellow solid (1.54 g, 85%): 1H NMR (400 MHz, CDCl3) δ 3.65 (2H, br s), 6.68 (1H, m), 6.98 (1H, dd, J 8.6, 11.0 Hz), 7.22-7.31 (2H, m), 7.71-7.83 (2H, m), 8.70 (1H, m); MS (ES+) m/z 189 [M+H]+.

Provenance & Evidence