反应详情

温度

50 °C

Benzoyl chloride (5.44 g, 38.73 mmol) was added to a stirred solution of ammonium thiocyanate (3.83 g, 50.35 mmol) in acetone (80 mL) at 30° C. The mixture was stirred at reflux for 30 minutes, then cooled to 50° C., and a solution of 3,5-difluoroaniline (5.00 g, 38.73 mmol) in acetone (10 mL) was added in one portion. The mixture was stirred at reflux for 30 minutes. A solution of NaOH (5.42 g, 135.54 mmol) in water (65 mL) was added, and the mixture was stirred at reflux for 20 minutes and then cooled to 20° C. Concentrated HCl was added to adjust the acidity to pH=5, and then the mixture was adjusted to slightly alkaline by the addition of conc. ammonium hydroxide. After 30 minutes, the mixture was cooled to 10° C. and extracted with EtOAc, and the combined organic layer was washed with brine, filtered, and concentrated to afford N-(3,5-difluorophenyl) thiourea (3.52 g, 48%). ret. time 1.73; m/z 189.0 (MH+); 1H NMR (400 MHz, MeOH-d4) δ 6.72 (m, 1H), 7.16 (m, 2H).

1. temperatureat reflux for 30 minutes
2. stirringThe mixture was stirred
3. temperatureat reflux for 30 minutes
4. stirringthe mixture was stirred
5. temperatureat reflux for 20 minutes
6. temperaturecooled to 20° C
7. temperaturethe mixture was cooled to 10° C.
8. extractionextracted with EtOAc
9. washthe combined organic layer was washed with brine
10. filtrationfiltered
11. concentrationconcentrated