反应详情

To a cooled concentrated sulfuric acid (10 ml) was added portionwise 5-amino-1-(2,4,6-trichlorophenyl)-1H-pyrazole-4-carbonitrile (4.000 g, 13.9 mmol) over a period of 45 minutes. The reaction mixture was allowed to stir at room temperature for 1 hour after addition. The mixture was poured over ice with stirring and the solution was neutralized with 15% NaOH in ice-bath. Precipitate formed and was filtered to give 3.57 g of yellow solid. 1H NMR (CDCl3): 5.3(brs,2H), 5.6(brs,2H), 7.5(s,2H), 7.7(s,1H)ppm.

1. additionafter addition
2. additionThe mixture was poured over ice
3. stirringwith stirring
4. customPrecipitate formed
5. filtrationwas filtered