反应详情

A mixture of 40.8 gm (0.091 mol) of N-(2-chloro-3-pyridinyl)-4-[[(4-methylphenyl)-sulfonyl]methylamino]-N,1,3-trimethyl-1H-pyrazole-5-carboxamide (prepared from N-(2-chloro-3-pyridinyl)-4-[[(4-methylphenyl)-sulfonyl]amino]-N,1,3-trimethyl-1H-pyrazole-5-carboxamide by reaction with sodium hydride in anhydrous N,N-dimethylformamide and subsequent reaction with methyl iodide) and 0.6 kg of polyphosphoric acid (content of phosphorpentoxide: 85%) was heated with stirring for 6 hours up to 60° C. The warm reaction mixture was stirred into cracked ice and subsequently mixed by means of external cooling with ice water with 40% aqueous sodium hydroxide solution until the precipitation was finished. After standing for 2 hours at +5° C., the strongly acidic reaction mixture was filtered off by suction filtration. The filtration residue was carefully washed with water and subsequently dried in the air. Yield: 20.9 gm (78% of theory).

1. temperaturewas heated
2. customThe warm reaction mixture
3. stirringwas stirred into cracked ice
4. additionsubsequently mixed by means
5. filtrationthe strongly acidic reaction mixture was filtered off by suction filtration
6. washThe filtration residue was carefully washed with water
7. customsubsequently dried in the air