反应详情

To a 40% aqueous solution of glyoxal (7.1 mL, 62 mmol) was added a solution of 2-oxopropanal methylhydrazone (6.17 g, 61.6 mmol) in water (300 mL). The mixture was heated at reflux for 1 hour before cooling to room temperature. The mixture was extracted with CH2Cl2 (4×). The combined organic extracts were dried over NaSO4, filtered, concentrated and purified by CombiFlash (120 g column, 30-40% EtOAc/hexanes gradient) to provide 1-(4-hydroxy-1-methyl-1H-pyrazol-3-yl)ethanone (5.93 g, 69%).

1. temperatureThe mixture was heated
2. temperatureat reflux for 1 hour
3. extractionThe mixture was extracted with CH2Cl2 (4×)
4. dry with materialThe combined organic extracts were dried over NaSO4
5. filtrationfiltered
6. concentrationconcentrated
7. custompurified by CombiFlash (120 g column, 30-40% EtOAc/hexanes gradient)