反应详情

温度

100 °C

A 250-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with 1,4-dioxane (60 mL), 5-bromo-2-nitropyridine (8.0 g, 31.8 mmol), pyridin-2-amine (1.0 g, 10.6 mmol), and cesium carbonate (7.0 g, 21.2 mmol). After bubbling nitrogen through the resulting mixture for 30 minutes, XantPhos (616 mg, 1.0 mmol) and tris(dibenzylideneacetone)dipalladium(0) (973 mg, 1.0 mmol) were added. The reaction mixture was subjected to three cycles of vacuum/argon flush and heated at 100° C. for 12 h. After this time the reaction was cooled to room temperature and filtered. The filtrate was partitioned between ethyl acetate (100 mL) and water (100 mL). The aqueous layer was separated and extracted with ethyl acetate (3×150 mL). The combined organic layer was washed with brine (50 mL) and dried over sodium sulfate. The drying agent was removed by filtration and the filtrate was concentrated under reduced pressure. The residue was purified on silica-gel column eluting with 30:1 dichloromethane/methanol to afford 178a (1.5 g, 51%) as yellow solid. MS: [M+H]+ 280

1. customA 250-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser
2. customAfter bubbling nitrogen through the resulting mixture for 30 minutes
3. customflush
4. temperatureAfter this time the reaction was cooled to room temperature
5. filtrationfiltered
6. customThe filtrate was partitioned between ethyl acetate (100 mL) and water (100 mL)
7. customThe aqueous layer was separated
8. extractionextracted with ethyl acetate (3×150 mL)
9. washThe combined organic layer was washed with brine (50 mL)
10. dry with materialdried over sodium sulfate
11. customThe drying agent was removed by filtration
12. concentrationthe filtrate was concentrated under reduced pressure
13. customThe residue was purified on silica-gel column
14. washeluting with 30:1 dichloromethane/methanol