反应详情

Lithium hydroxide (62 mg, 2.6 mmol) was added to a solution of ethyl 3-tert-butyl-1-(quinolin-6-yl)-1H-pyrazole-5-carboxylate (0.21 g, 0.65 mmol) in dioxane-H2O-EtOH (1:1:1, 6 mL). The reaction mixture was stirred overnight at RT. The solution was concentrated and the residue was dissolved in H2O (2 mL). 3M HCl was added and the precipitate was collected by filtration and washed with water. The solid was dried under vacuum to obtain 3-tert-butyl-1-(quinolin-6-yl)-1H-pyrazole-5-carboxylic acid (0.18 g, 94% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ 8.96 (dd, J=2.0, 4.0 Hz, 1H), 8.47 (dd, J=1.2, 8.4 Hz, 1H), 8.09 (m, 1H), 8.06 (s, 1H), 7.82 (dd, J=2.8, 9.2 Hz, 1H), 7.61 (dd, J=4.8, 8.8 Hz, 1H), 7.01 (s, 1H), 1.33 (s, 9H); MS (ESI) m/z: 296.0 (M+H+).

1. concentrationThe solution was concentrated
2. dissolutionthe residue was dissolved in H2O (2 mL)
3. addition3M HCl was added
4. filtrationthe precipitate was collected by filtration
5. washwashed with water
6. customThe solid was dried under vacuum