反应详情

To a solution of 3-(2-bromo-phenyl)-3-oxo-propionitrile (1.8 g, 8.03 mmol) in absolute EtOH (25 mL) was added hydrazine hydrate (2.3 mL, 48.2 mmol). The reaction mixture was refluxed for 23 hours, then cooled and purified directly on silica gel with 0-10% MeOH in CH2Cl2 as eluent to provide 1.33 g (70% yield) of 5-amino-3-(2-bromophenyl)pyrazole as a sticky oil. 1H-NMR (d6-DMSO) δ: 11.7 (broad m, 1H, tautomers), 7.20-7.70 (broad m, 4H), 5.76 (broad m, 1H), 5.03 (broad s, 1H), 4.60 (broad s, 1H); HPLC/MS m/z: 238.0, 240.0 [MH]+.

1. temperatureThe reaction mixture was refluxed for 23 hours
2. temperaturecooled
3. custompurified directly on silica gel with 0-10% MeOH in CH2Cl2 as eluent