反应详情

温度

100 °C

A stirred mixture of 5-amino-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethylsulfonyl-1 H-pyrazole-3-carbonitrile (1.06 g, 2.21 mmol) and concentrated sulfuric acid (1 ml) was heated to 100° C. for 3 hours. The cooled mixture was added to ice water and the precipitate filtered off, washed with water and air-dried. Purification by flash chomatography (silica, chloroform) gave the title compound (0.869 g, yield 83%) as off-white crystals, mp 217° C., 1H NMR (DMSO-d6): 7.39 (bs, 2H, NH2), 7.57 and 7.78 (bs, 2H, C(O)NH2), and 8.25 (s, 2H, Ar—H).

1. filtrationthe precipitate filtered off
2. washwashed with water
3. customair-dried
4. customPurification by flash chomatography (silica, chloroform)