反应详情

温度

225 °C

The crude 5-methoxy-4-nitroindole-2-carboxylic acid (720 mg, 3.05 mmol), quinoline (9 ml) and copper chromite (180 mg) were stirred together. Nitrogen was gently bubbled through the mixture for 5 minutes, then the mixture was heated quickly to 225° C., and stirred at this temperature for 40 minutes under an atmosphere of nitrogen. The mixture was cooled to ambient temperature diluted with ethyl acetate (80 ml) and the insoluble material filtered off. The filtrate was extracted twice with aqueous hydrochloric acid (2M) and then with saturated aqueous sodium hydrogen carbonate solution. The ethyl acetate layer was dried (MgSO4), evaporated and the residue purified by silica column chromatography eluting with dichloromethane to give 5-methoxy-4-nitroindole (129 mg, 22%).

1. customNitrogen was gently bubbled through the mixture for 5 minutes
2. temperatureThe mixture was cooled to ambient temperature
3. additiondiluted with ethyl acetate (80 ml)
4. filtrationthe insoluble material filtered off
5. extractionThe filtrate was extracted twice with aqueous hydrochloric acid (2M)
6. dry with materialThe ethyl acetate layer was dried (MgSO4)
7. customevaporated
8. customthe residue purified by silica column chromatography
9. washeluting with dichloromethane