反应详情

Similar to Example 1, o-nitrophenylhydrazine (20 mmol, 3.4 g) and 2-acetyl-3-oxo-butyric acid ethyl ester (20 mmol, 3.4 g) were mixed in a solution of 50% pyridine in ethanol and heated under reflux. The solvents then were removed under vacuum, and the residue was resuspended in chloroform. The resulting mixture was washed with water and dried over NaSO4. The solids then were filtered, and the solvents removed under vacuum. A precipitate formed when the oily solid was dissolved in a solution of 20% hexane in chloroform. The solid was collected and discarded, and the filtrate was purified over silica gel. The named product was contaminated, then was further purified by recrystallization from ethanol to yield a solid having a melting point of 128° C.-130° C.

1. temperatureheated
2. temperatureunder reflux
3. customThe solvents then were removed under vacuum
4. washThe resulting mixture was washed with water
5. dry with materialdried over NaSO4
6. filtrationThe solids then were filtered
7. customthe solvents removed under vacuum
8. customA precipitate formed when the oily solid
9. customThe solid was collected
10. customthe filtrate was purified over silica gel
11. customwas further purified by recrystallization from ethanol
12. customto yield a solid