反应详情

1H-pyrazol-3-amine (ALDRICH, 11.32 g, 0.136 mol) was dissolved in 100 mL of distilled water. NaHCO3 (34 g, 0.408 mol) was slowly added. Acetic anhydride was then added dropwise and the resulting suspension was heated at reflux overnight. Then, the mixture was allowed to cool down to room temperature and the solid obtained was filtered off and characterized as the title compound (8.4 g, 0.067 mol, 49% yield). After concentration of the filtrate, a second precipitate was obtained (2.7 g, 0.021 mol, 16% yield), also characterized as the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm: 12.23 (br s, 1H), 10.30 (br s, 1H), 7.55 (br s, 1H), 6.45 (br s, 1H), 1.97 (s, 3H). [ES+MS] m/z 126 (MH+).

1. temperaturethe resulting suspension was heated
2. temperatureat reflux overnight
3. customthe solid obtained
4. filtrationwas filtered off