25391-56-4

Useful starter in azaindole chemistry.

General procedure for the synthesis of 2-amino-3-iodo-5-nitropyridine from 2-amino-5-nitropyridine: 5-nitropyridin-2-amine (14 g, 100 mmol), potassium iodide (16.6 g, 100 mmol) and potassium iodate (10.7 g, 50 mmol) were dissolved in dilute sulfuric acid (2 N, 200 mL). The reaction mixture was stirred at 80 °C overnight. Upon completion of the reaction, the pH was adjusted slowly by adding sodium hydroxide solution (5 N, 80 mL) to about 10. The resulting solid product was collected by filtration, washed sequentially with deionized water and ethanol and finally dried under vacuum. The target compound 2-amino-3-iodo-5-nitropyridine (25 g, 94% yield) was obtained. The structure of the product was characterized by 1H NMR (300 MHz, DMSO-d6) and mass spectrometry (ESI): 1H NMR δ 6.80-8.40 (br s, 2H), 8.57 (d, J = 2.4 Hz, 1H), 8.84 (d, J = 2.4 Hz, 1H); MS (ESI) m/z 264 [M+H]+.

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