Hydrochloric Acid → 3-Methoxy-1-methyl-1H-pyrazole-5-carboxylic acid

To a solution of methyl 3-methoxy-1-methyl-1H-pyrazole-5-carboxylate (2.01 g, 11.8 mmol) in methanol (15 mL) was added 8N aqueous sodium hydroxide solution (3.00 mL), and the mixture was stirred at room temperature for 18 hr. 6N Hydrochloric acid (4.00 mL) was added to the mixture, and the mixture was concentrated under reduced pressure. Water was added to the residue, and the precipitate was collected by filtration, washed with water and air-dried. The precipitate was suspended in diisopropyl ether, and the mixture was stirred at 80° C. for 15 min. After allowing to cool to room temperature, the precipitate was collected by filtration, washed with diisopropyl ether, and dried under reduced pressure to give the title compound (746 mg, yield 40%) as a white solid.

1. concentrationthe mixture was concentrated under reduced pressure
2. additionWater was added to the residue
3. filtrationthe precipitate was collected by filtration
4. washwashed with water
5. customair-dried
6. stirringthe mixture was stirred at 80° C. for 15 min
7. temperatureto cool to room temperature
8. filtrationthe precipitate was collected by filtration
9. washwashed with diisopropyl ether
10. customdried under reduced pressure

ORD record

ord-696dedaaee09413a9e45c774acb36a06

Source dataset

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08044049B2