反应详情

(2-Fluoro-4-methanesulfonyl-phenyl)-hydrazine (1 g, 4.89 mmol) and sodium methoxide (30 mg, 0.489 mmol) were dissolved in methanol under N2 at room temperature. The mixture was stirred for 10. min and 2-ethoxymethylene-malononitrile (0.6 g, 4.91 mmol) was added. The reaction mixture was stirred for 30 min and then brought to reflux for 2 hours. The solvent was removed under reduced pressure; the residue was suspended in water and extracted with ethyl acetate. The organic layer was washed with water, brine and was dried over sodium sulfate. The solvent was concentrated, affording 5-amino-1-(2-fluoro-4-methanesulfonyl-phenyl)-1H-pyrazole-4-carbonitrile as a yellow solid (1.2 g, 87.5%). 1H NMR (400MHz DMSO-d6) δ (ppm): 7.96 (d, 1H); 7.93 (m, 1H); 7.80 (s, 1H); 7.74 (m, 1H); 6.89 (s, 2H); 3.24(s, 3H). Exact mass calculated for C11H9FN4O2S 280.04, found 281.30 (MH+, 100%).

1. stirringThe reaction mixture was stirred for 30 min
2. temperatureto reflux for 2 hours
3. customThe solvent was removed under reduced pressure
4. extractionextracted with ethyl acetate
5. washThe organic layer was washed with water, brine
6. dry with materialwas dried over sodium sulfate
7. concentrationThe solvent was concentrated