反应详情

A 250-mL three-neck round-bottomed flask equipped with a reflux condenser, magnetic stirrer and nitrogen inlet was charged with 2-aminopyrimidine (376 mg, 3.95 mmol), 3,5-dibromo pyridin-2(1H)-one (1.00 g, 3.95 mmol), 1 M THF solution of lithium hexamethyldisilazide (20 mL, 20.0 mmol), and 1,4-dioxane (25 mL). After bubbling nitrogen through the resulting suspension for 30 min, Xantphos (194 mg, 0.211 mmol) and tris(dibenzylideneacetone)dipalladium(0) (165 mg, 0.197 mmol) were added, and the reaction mixture was heated at reflux for 3 h. After this time, the mixture was cooled to room temperature and diluted with ethyl acetate (150 mL) and water (30 mL). The organic layer was separated, and the aqueous layer was extracted with ethyl acetate (3×150 mL). The combined organic extracts were dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by flash chromatography followed by trituration with ethyl acetate (20 mL) to afford a 24% yield (250 mg) of 154a as an off-white solid: mp 150-151° C.; 1H NMR (500 MHz, DMSO-d6) d 12.03 (s, 1H), 9.27 (s, 1H), 8.54 (s, 1H), 8.20 (d, 1H, J=6.0 Hz), 7.85 (s, 1H), 6.64 (d, 1H, J=6.0 Hz); MS (ESI+) m/z 268.2 (M+H).

1. customA 250-mL three-neck round-bottomed flask equipped with a reflux condenser, magnetic stirrer and nitrogen inlet
2. customAfter bubbling nitrogen through the resulting suspension for 30 min
3. temperaturethe reaction mixture was heated
4. temperatureat reflux for 3 h
5. customThe organic layer was separated
6. extractionthe aqueous layer was extracted with ethyl acetate (3×150 mL)
7. dry with materialThe combined organic extracts were dried over sodium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by flash chromatography