反应详情

温度

100 °C

A suspension of 6-chloro-3-hydrazinylpyridazine-4-carboxylic acid (4.8 g; crude product) in AcOH (100 mL) was heated at 100° C. for 3 h. The mixture was cooled to room temperature and concentrated to remove the solvent. Then the residue was washed by petroleum ether (50 mL) and recrystallized from MeOH to give the pure 6-chloro-3-methyl-[1,2,4]triazolo[4,3-b]pyridazine-8-carboxylic acid (4.0 g, 73% yield over two steps). 1H NMR (300 MHz, DMSO-d6): δ 7.2 (s, 1H), 2.66 (s, 3H). LRMS [M+H]+: 212 m/z.

1. temperatureThe mixture was cooled to room temperature
2. concentrationconcentrated
3. customto remove the solvent
4. washThen the residue was washed by petroleum ether (50 mL)
5. customrecrystallized from MeOH