反应详情

To a solution of 5-(2-fluoro-4-methoxyphenyl)-6-methyl-1H-indazole-3-carboxylic acid ethyl ester (292 mg, 0.89 mmol) in THF (4 mL) was added a solution of LiOH (298.0 mg, 12.25 mmol) in water (2 mL). The reaction mixture was heated to reflux for 9 hours, and stirred at room temperature for an additional 48 hours. 1 N HCl solution was added to acidify the solution to pH 2. White solid formed, which was collected with filtration and dried in a vacuum oven at 50° C. for 4 hours to give the title compound (240 mg, 90% yield) as a solid. MS (ES+) 301.2 (M+H)+. 1H NMR (500 MHz, CD3OD) δ 7.92 (s, 1H), 7.51 (s, 1H), 7.22 (dd, J=8.70, 8.70 Hz, 1H), 6.87 (dd, J=8.42, 2.56 Hz, 1H), 6.81 (dd, J=11.59, 2.56 Hz, 1H), 3.88 (s, 3H), 2.30 (s, 3H).

1. temperatureThe reaction mixture was heated
2. temperatureto reflux for 9 hours
3. customWhite solid formed
4. filtrationwhich was collected with filtration
5. customdried in a vacuum oven at 50° C. for 4 hours