反应详情

3-(4-chloro-2-thienyl)-1H-pyrazole (24.0 mmol) was dissolved in 50 mL N,N-dimethylformamide under argon atmosphere. N-Iodosuccinimide (25.1 mmol) was added in small portions. The reaction mixture was stirred at room temperature overnight. 5% aqueous sodium thiosulfate solution and saturated aqueous sodium carbonate solution were added and the mixture was stirred at room temperature for 1 h. The white precipitate was filtered, washed thoroughly with water and dried in vacuum to afford 6.80 g of 3-(4-chloro-2-thienyl)-4-iodo-1H-pyrazole (91% yield) that was used without further purification.

1. stirringthe mixture was stirred at room temperature for 1 h
2. filtrationThe white precipitate was filtered
3. washwashed thoroughly with water
4. customdried in vacuum