反应详情

To a stirred solution of 4-bromo-2-methylpyridine (2.9 g, 16.8 mmol) and methyl 4-methoxybenzoate (2.8 g, 16.8 mmol) in tetrahydrofuran (42 mL) at 0° C. was added dropwise a 1M solution of lithium bis(trimethylsilyl)amide (33.6 mL, 33.6 mmol). The mixture was allowed to warm to room temperature and stirred for 3 days. A saturated solution of ammonium chloride (40 mL) was added and the mixture was diluted with ethyl acetate (50 mL). The separated aqueous layer was then extracted with ethyl acetate (3×25 mL). The combined organic layers were washed with brine, dried over anhydrous MgSO4, filtered and concentrated under reduced pressure to afford a residue which was purified by automated flash-chromatography (ethyl acetate/hexanes; 15/85). The title compound was obtained as a bright yellow solid (3.8 g, 75%). LCMS m/z 306.0; 308.0 (M+H)+, ret. time=2.48 min.

1. extractionThe separated aqueous layer was then extracted with ethyl acetate (3×25 mL)
2. washThe combined organic layers were washed with brine
3. dry with materialdried over anhydrous MgSO4
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customto afford a residue which
7. customwas purified by automated flash-chromatography (ethyl acetate/hexanes; 15/85)