反应详情

To a solution of 5-(2-chlorophenyl)-2H-pyrazol-3-ylamine (I-1A-1a; 1.51 g, 7.80 mmol) in acetic acid (10 ml) was added ethyl acetoacetate (1.1 ml, 8.6 mmol). The reaction was heated at reflux for 17 hours. Upon cooling to room temperature a solid precipitate formed which, after standing for 2 days, was isolated by vacuum filtration and washed with additional acetic acid. The solids were stirred in ether and then isolated by vacuum filtration to afford I-1A-3f as a colorless solid (1.52 g, 75%): +ESI MS (M+1) 260.2; 1H NMR (400 MHz, DMSO-d6) δ 12.18 (br s, 1H), 7.85–7.81 (m, 1H), 7.57–7.54 (m, 1H), 7.46–7.41 (m, 2H), 6.49 (s, 1H), 5.61 (s, 1H), 2.29 (s, 3H).

1. temperatureThe reaction was heated
2. temperatureat reflux for 17 hours
3. customformed which
4. customwas isolated by vacuum filtration
5. washwashed with additional acetic acid
6. customisolated by vacuum filtration