反应详情

A 250-mL round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with 199a (2.2 g, 16.4 mmol), 3,5-dibromo-1-methylpyridin-2(1H)-one (8.77 g, 32.8 mmol), Pd2dba3 (1.5 g, 1.64 mmol), Xantphos (1.88 g, 3.28 mmol), Cs2CO3 (10.7 g. 32.8 mmol), and 1,4-dioxane (150 mL). The system was evacuated and then refilled with N2. It was then heated at reflux for 3 h. After the completion of the reaction, the mixture was filtered off and the solid was washed with methanol (60 mL). The combined filtrate was evaporated under reduced pressure and the residue was purified by silica-gel column chromatography eluting with 20:1 dichloromethane/methanol to afford 199b as a light green solid (1.63 g, 31%). MS: [M+H]+ 320.1

1. customA 250-mL round-bottomed flask equipped with a magnetic stirrer and a reflux condenser
2. customThe system was evacuated
3. additionrefilled with N2
4. temperatureIt was then heated
5. temperatureat reflux for 3 h
6. customAfter the completion of the reaction
7. filtrationthe mixture was filtered off
8. washthe solid was washed with methanol (60 mL)
9. customThe combined filtrate was evaporated under reduced pressure
10. customthe residue was purified by silica-gel column chromatography
11. washeluting with 20:1 dichloromethane/methanol