反应详情

1-(3-Pyridinyl)-1-ethanone hydrazone (Preparation 76, 0.69 g, 5.3 mmol) was dissolved in dioxan (30 ml) and manganese dioxide (0.85 g, 5.3 mmol) was added portionwise followed by a saturated solution of potassium hydroxide in ethanol (0.5 ml). The reaction mixture was stirred at room temperature for 1.5 h and then filtered through a pad of Celite®. To half of the filtrate was added 1-hexyl-1H-pyrrole-2,5-dione (Preparation 56, 0.48 g, 2.6 mmol) and the reaction mixture was heated to 90° C. for 7 h and then cooled to room temperature for 16 h. The reaction mixture was heated under reflux for 16 h and then stirred at room temperature for 72 h before concentrating in vacuo, The reaction mixture was purified by chromatography using silica gel (30 g) eluting with dichloromethane:0.880 ammonia (99:1) and then dichloromethane:methanol: 0.880 ammonia (97:2:1) to afford the title compound (0.22 g, 29%).

1. filtrationfiltered through a pad of Celite®
2. temperaturethe reaction mixture was heated to 90° C. for 7 h
3. temperaturecooled to room temperature for 16 h
4. temperatureThe reaction mixture was heated
5. temperatureunder reflux for 16 h
6. stirringstirred at room temperature for 72 h
7. concentrationbefore concentrating in vacuo
8. customThe reaction mixture was purified by chromatography
9. washeluting with dichloromethane