反应详情

To a suspension of 2-bromo4-pyridine carboxylic acid (prepared according to the method of Ashimori, Chem. Pharm. Bull. 38 (9) 2446-2458 (1990)) in 2:1 toluene: absolute ethanol (45 mL) was added sulfuric acid (0.75 mL). The mixture was heated at reflux for 16 h. The mixture was poured into saturated aqueous sodium bicarbonate and extracted with chloroform (3 times). The combined chloroform extracts were dried over magnesium sulfate, filtered and concentrated afforded the crude product as a yellow oil. Purification by silica gel chromatography eluting with 9:1 hexane:ethyl acetate to afford the title compound (900 mg) as a clear, colorless oil.

1. customprepared
2. temperatureThe mixture was heated
3. temperatureat reflux for 16 h
4. extractionextracted with chloroform (3 times)
5. dry with materialThe combined chloroform extracts were dried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customafforded the crude product as a yellow oil
9. customPurification by silica gel chromatography
10. washeluting with 9:1 hexane