63572-73-6

The general procedure for the synthesis of 5-nitro-7-azaindazole from the sodium salt of nitromalonaldehyde and 3H-pyrazol-3-amine was as follows: 3H-pyrazol-3-amine (0.804 g, 9.48 mmol) and nitromalonaldehyde monohydrate (1.56 g, 9.96 mmol) were suspended in acetic acid (12 mL), and the mixture was heated to 90 °C and stirred overnight. Upon completion of the reaction, the mixture was cooled to room temperature and subsequently poured into water (50 mL). The resulting solid product was collected by filtration and the solid was washed with distilled water (3 x 20 mL). Finally, the solid was dried under vacuum to afford 5-nitro-1H-pyrazolo[3,4-b]pyridine (1.40 g, 84% yield) as a solid product.

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