反应详情

A 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer and reflux condenser was charged with 1,4-dioxane (60 mL), 336f (crude, 14.1 mmol), 3,5-dibromo-1-methylpyridin-2(1H)-one (4.5 g, 16.9 mmol), and cesium carbonate (11.5 g, 35.2 mmol). After bubbling nitrogen through the resulting solution for 30 min, Xantphos (820 mg, 1.41 mmol) and tris(dibenzylideneacetone)dipalladium(0) (645 mg, 0.7 mmol) were added. After three cycles of vacuum/argon flash, the reaction mixture was heated at reflux for 15 h. The reaction was cooled to room temperature, filtered and concentrated to afford a black solid, which was purified by column chromatography eluting with methylene chloride/methanol (from 100:1 to 50:1) to afford 336g as a yellow solid (3.1 g, 50%). MS: [M+H]+ 410.

1. customA 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer
2. temperaturereflux condenser
3. customAfter bubbling nitrogen through the resulting solution for 30 min
4. temperatureAfter three cycles of vacuum/argon flash, the reaction mixture was heated
5. temperatureat reflux for 15 h
6. filtrationfiltered
7. concentrationconcentrated
8. customto afford a black solid, which
9. customwas purified by column chromatography
10. washeluting with methylene chloride/methanol (from 100:1 to 50:1)