反应详情

A 1-L round-bottomed flask equipped with a magnetic stirrer was charged with 3,5-dibromo-1H-pyridin-2-one (7.0 g, 27.7 mmol), anhydrous DMF (280 mL) and powdered potassium carbonate (−350 mesh, 8.4 g, 61.1 mmol), and the suspension stirred for 15 min at ambient temperature. After this time, methyl iodide (4.3 g, 30.5 mmol) was added, and the mixture was stirred at room temperature under nitrogen for an additional 18 h. The reaction mixture was then diluted with water (200 mL), extracted with ethyl acetate (3×250 mL), dried over sodium sulfate and concentrated in vacuo. The resulting residue was purified by flash chromatography on silica to give an 84% yield (6.2 g) of 3,5-dibromo-1-methyl-1H-pyridin-2-one (1) as an off-white solid; mp 87-88° C.; MS (ESI+) m/z 266 (M+H).

1. customA 1-L round-bottomed flask equipped with a magnetic stirrer
2. stirringthe mixture was stirred at room temperature under nitrogen for an additional 18 h
3. extractionextracted with ethyl acetate (3×250 mL)
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated in vacuo
6. customThe resulting residue was purified by flash chromatography on silica