反应详情

To a solution of methyl 4-(1H-pyrazol-1-yl)benzoate of Step A (0.529 g, 2.62 mmol) in methanol (20 mL) and water (4 mL) was added lithium hydroxide monohydrate (0.220 g, 5.23 mmol) and the reaction mixture heated to reflux for 2 hours. The cooled reaction mixture was concentrated in vacuo to remove methanol and then diluted with water (40 mL). The resulting aqueous solution was washed with diethyl ether (40 mL), then acidified to pH 3 by the addition of concentrated hydrochloric acid. The solid product was filtered and dried in vacuo at 50° C. overnight to afford the title compound (0.479 g, 97%) as a white solid, m.p. 270-272° C.

1. temperaturethe reaction mixture heated
2. temperatureto reflux for 2 hours
3. customThe cooled reaction mixture
4. concentrationwas concentrated in vacuo
5. customto remove methanol
6. additiondiluted with water (40 mL)
7. washThe resulting aqueous solution was washed with diethyl ether (40 mL)
8. additionacidified to pH 3 by the addition of concentrated hydrochloric acid
9. filtrationThe solid product was filtered
10. customdried in vacuo at 50° C. overnight