(Step 3) (1068) 3-Chloro-5-nitropyridine-2-carbonitrile (0.18 g, 0.984 mmol) was dissolved in ethanol (6.0 mL), and stannic chloride (II) (0.929 g, 4.918 mmol) was added. The reaction mixture was heated to reflux for 2 hours. After completion of the reaction, it was cooled to room temperature and the pH was adjusted with saturated aqueous sodium bicarbonate to 7. The reaction mixture was extracted with ethyl acetate (3×), the organic layer was washed sequentially with water and saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure to give 5-amino-3-chloropyridine-2-carbonitrile (0.13 g, 87% yield) as an off-white solid.1H-NMR (400 MHz, DMSO-d6): δ 6.77 (broad single peak, 2H), 7.05 (d, 1H, J=2.32 Hz), 7.94 (d, 1H, J=2.28 Hz).
