反应详情

A mixture of 2-ethylpyridin-5-amine (3.2 g, 26 mmol), 2,5-hexanedione (3.0 g, 26 mmol) and acetic acid (1 ml) in toluene (50 ml) was heated under reflux for 24 hours. The solvent was removed under reduced pressure and the residue was partitioned between dichloromethane (50 ml) and water (20 ml). The aqueous phase was basified with aqueous sodium hydroxide (2M) and then extracted with dichloromethane (50 ml). The extract was dried (MgSO4) and evaporated under reduced pressure. The crude product was purified by column chromatography on silica by elution with dichloromethane/methanol (95:5) to give the title compound (2.38 g, 46%) as a colourless oil, which was characterised by 1H-N.M.R. spectroscopy.

1. temperaturewas heated
2. temperatureunder reflux for 24 hours
3. customThe solvent was removed under reduced pressure
4. customthe residue was partitioned between dichloromethane (50 ml) and water (20 ml)
5. extractionextracted with dichloromethane (50 ml)
6. dry with materialThe extract was dried (MgSO4)
7. customevaporated under reduced pressure
8. customThe crude product was purified by column chromatography on silica by elution with dichloromethane/methanol (95:5)