171178-21-5

Step 2) Preparation of 6-chloro-3-nitropyridinecarboxamide: A mixture of 6-chloro-3-nitropyridinecarbonitrile (12 g, 65.4 mmol) and tin(II) chloride dihydrate (59 g, 262 mmol) in ethanol (144 mL) was heated to 85°C and the reaction was carried out for 3 hours. Upon completion of the reaction, the solution was concentrated under reduced pressure, diluted with the addition of water, followed by the slow addition of saturated aqueous sodium bicarbonate to adjust the pH to 8. The mixture was extracted several times with ethyl acetate, and the organic layers were combined and dried over anhydrous sodium sulfate. Finally, the organic layer was concentrated under reduced pressure to give 6-chloro-3-nitropyridinecarboxamide in quantitative yield.

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