反应详情

温度

50 °C

Lithium hydroxide monohydrate (0.373 g, 8.90 mmol) was added to ethyl 4-[4-[3-(trifluoromethyl)[1,2,4]triazolo[4,3-b]pyridazin-6-yl]piperazin-1-yl]benzoate (3.40 g, 8.09 mmol) in a mixture of MeOH (60 mL) and water (30 mL). The resulting suspension was stirred at 50° C. for 16 hours. Further lithium hydroxide monohydrate (0.373 g, 8.90 mmol) was added, the temperature was increased to 65° C. and the suspension was stirred for a further 6 hours. The reaction mixture was cooled to room temperature and the MeOH evaporated. The residues were dissolved in water (200 mL) and filtered. The filtrate was acidified with 1M citric acid until precipitation ceased, and the precipitate was collected by filtration, washed with water and dried under vacuum to afford 4-[4-[3-(trifluoromethyl)[1,2,4]triazolo[4,3-b]pyridazin-6-yl]piperazin-1-yl]benzoic acid (3.17 g, 100%) as a solid.

1. temperaturethe temperature was increased to 65° C.
2. stirringthe suspension was stirred for a further 6 hours
3. temperatureThe reaction mixture was cooled to room temperature
4. customthe MeOH evaporated
5. dissolutionThe residues were dissolved in water (200 mL)
6. filtrationfiltered
7. customThe filtrate was acidified with 1M citric acid until precipitation
8. filtrationthe precipitate was collected by filtration
9. washwashed with water
10. customdried under vacuum