Hydrazine → 4-Iodo-1H-pyrazolo[3,4-b]pyridine

Participants

Reaction Conditions

Reaction Steps

To a cooled solution of 2-fluoro-4-iodonicotinaldehyde (19.75 g, 78.7 mmol) in anhydrous tetrahydrofuran (100 ml) at 10° C. was carefully added 1M hydrazine in tetrahydrofuran (100 ml, 100 mmol) at such a rate that the temperature of the reaction mixture remained below 30° C. After complete addition a precipitate started to form and this was allowed to stir for a few minutes and then the vessel was sealed and heated to 90° C. for 2 hours behind a blast shield. After this time, the reaction mixture was allowed to cool down to room temperature and concentrated to dryness. The resulting yellow solid was triturated with a small amount of ethyl acetate to give the product as a pale yellow powder (17.68 g, 92% yield).

Provenance & Evidence