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. 1N 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