反应详情

Method A A stirred solution of 4,5-dimethylphenylenediamine (4.32 g) and diisopropylethylamine (30 ml) in dichloromethane (200 ml) was treated with 4-nitropyrazole-3-carboxylic chloride (5 g) portionwise at 0° C. The reaction mixture was warmed to ambient temperature and stirred for 30 minutes. The solvent was removed in vacuo and the oily residue was partitioned between ethyl acetate and water. The organic layer was dried over magnesium sulfate and concentrated. The residual oil was re-crystallised from ethyl acetate and methanol (10%) to give 4-nitro-1H-pyrazole-3-carboxylic acid (2-amino-4,5-dimethylphenyl)amide (6.58 g) as an orange solid. LC-MS (METHOD B): RT=2.36 minutes, 276.09 (M+H)+.

1. customThe solvent was removed in vacuo
2. customthe oily residue was partitioned between ethyl acetate and water
3. dry with materialThe organic layer was dried over magnesium sulfate
4. concentrationconcentrated
5. customThe residual oil was re-crystallised from ethyl acetate and methanol (10%)