反应详情

温度

45 °C

To a solution of ethanol (15 mL) and ether (150 mL) were added 5-bromo-2-methoxy-4-methyl-3-nitropyridine (14.82 g, 60 mmol), diethyl oxalate (13.15 g, 90 mmol), and potassium ethoxide (6.06 g, 72 mmol). The reaction mixture was heated at 45° C. for 24 hours. During the reaction, the flask was shaken by hand several times. After cooling, the reaction mixture was partitioned between water and ethyl acetate. The aqueous layer was extracted with additional ethyl acetate three times. The combined organic layers were washed with brine, dried over MgSO4, filtered, and concentrated. The residue was purified by flash chromatography on silica gel eluting with 10-20% ethyl acetate in hexanes to 9.5 g of the title compound (yield 46%).

1. customDuring the reaction
2. temperatureAfter cooling
3. customthe reaction mixture was partitioned between water and ethyl acetate
4. extractionThe aqueous layer was extracted with additional ethyl acetate three times
5. washThe combined organic layers were washed with brine
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated