反应详情

温度

80 °C

Cyclopentyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid ethyl ester (0.237 g, 0.858 mmol) was dissolved in methanol (2.0 mL). Water (2.0 mL) and lithium hydroxide (0.027 g, 1.127 mmol) were added and the mixture was heated at 80° C. for 2 hours. After cooling to room temperature, the methanol was removed in vacuo. THF was added to the residue and then removed in vacuo to insure complete removal of the methanol. 6N HCl (0.2 mL) was added to the aqueous residue to pH 2-3 resulting in precipitation of a white solid. The solid was collected by filtration, washed with water and dried under high vacuum at 100° C. to give 1-cyclopentyl-5-trifluoromethyl-1H-pyrazole-4-carboxylic acid (0.134 g, 63%).

1. temperatureAfter cooling to room temperature
2. customthe methanol was removed in vacuo
3. additionTHF was added to the residue
4. customremoved in vacuo
5. customremoval of the methanol
6. addition6N HCl (0.2 mL) was added to the aqueous residue to pH 2-3
7. customresulting in precipitation of a white solid
8. filtrationThe solid was collected by filtration
9. washwashed with water
10. customdried under high vacuum at 100° C.