反应详情

To a mixture of 2-(4-fluorophenyl)-6-(trifluoromethyl)pyrazolo[1,5-a]pyridine (10.30 g, 36.76 mmol) and acetic anhydride (100 mL) was added conc. sulfuric acid (10 drops) and the mixture was stirred and heated at reflux for 1 hour. The reaction mixture was cooled to room temperature and poured into ice water (300 mL). 2N Aqueous sodium hydroxide solution was added to raise the pH of the solution to about 10 and the resulting orange precipitate was collected by filtration. The solid was washed with water, air-dried, and then dried under vacuum to afford the title compound as an orange solid, 11.87 g (quant.). 1H NMR (DMSO-d6): δ 9.58 (s, 1H), 8.41 (d, 1H, J=9.3 Hz), 7.89 (d, 1H, J=9.5 Hz), 7.74 (m, 2H), 7.39 (m, 2H), 2.22 (s, 3H). MS (ES) 323 (M+1).

1. temperatureheated
2. temperatureat reflux for 1 hour
3. temperatureto raise the pH of the solution to about 10
4. filtrationthe resulting orange precipitate was collected by filtration
5. washThe solid was washed with water
6. customair-dried
7. customdried under vacuum