反应详情

温度

88 °C

Concentrated sulfuric acid (0.04 mL, 0.75 mmol) was added to a solution of (6-hydroxy-3-oxo-2,3-dihydro-pyridazin-4-yl)-acetic acid (Example 182-(1); 259 mg, 1.52 mmol) in ethanol (3.2 mL), and the mixture was heated while stirring at an external temperature of 84 to 92° C. for four hours. The mixture was left to stand at room temperature overnight. Then, the resulting solid was collected by filtration and sequentially washed with water and ether to give the title compound (246 mg, 82%).

1. temperaturethe mixture was heated
2. waitThe mixture was left
3. waitto stand at room temperature overnight
4. filtrationThen, the resulting solid was collected by filtration
5. washsequentially washed with water and ether