反应详情

To a solution of 3-phenyl-1H-pyrazol-5-amine (4 g, 25.1 mmol) and dimethyl 2-acetylsuccinate (12 mL, 74.0 mmol) in xylene (120 mL) was added p-toluenesulfonic acid monohydrate (50 mg, 0.263 mmol). The reaction mixture was heated at reflux under a Dean-Stark trap for 20 h. The solid was filtered and washed with hexanes to afford the title compound (6.4 g, 86%). 1H-NMR (400 MHz, MeOD) δ ppm 2.37 (3H, s), 3.66 (2H, s), 3.72 (3H, s), 6.46 (1H, s), 7.34-7.53 (3H, m), 7.87-8.06 (2H, m).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux under a Dean-Stark trap for 20 h
3. filtrationThe solid was filtered
4. washwashed with hexanes