反应详情

温度

120 °C

To ethyl 4-chloropyridine-2-carboxylate (19.4 g) were added 3-fluoro-4-nitrophenol (24.7 g) and chlorobenzene (7.0 ml), followed by heating and stirring under a nitrogen atmosphere at 120° C. for 4 hr. The reaction mixture was allowed to cool down to room temperature. Ethyl acetate (400 ml) and a saturated aqueous solution of sodium hydrogencarbonate (400 ml) were added thereto, followed by stirring at room temperature for 27 hr. Stirring was stopped and the aqueous layer was separated. To the organic layer was added again a saturated aqueous solution of sodium hydrogencarbonate, followed by stirring at room temperature for 2 days. Stirring was stopped and the aqueous layer was separated. The aqueous layer was extracted with ethyl acetate (300 ml). The organic layers were combined and washed with brine. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent; heptane:ethyl acetate=2:1, 1:1, then ethyl acetate). Fractions containing the target compound were concentrated to provide the titled compound as a brown oil (12.9 g, 40.2%).

1. temperatureby heating
2. temperatureto cool down to room temperature
3. stirringby stirring at room temperature for 27 hr
4. stirringStirring
5. customthe aqueous layer was separated
6. additionTo the organic layer was added again a saturated aqueous solution of sodium hydrogencarbonate
7. stirringby stirring at room temperature for 2 days
8. stirringStirring
9. customthe aqueous layer was separated
10. extractionThe aqueous layer was extracted with ethyl acetate (300 ml)
11. washwashed with brine
12. dry with materialThe organic layer was dried over anhydrous sodium sulfate
13. concentrationconcentrated under reduced pressure
14. customThe residue was purified by silica gel column chromatography (eluent
15. additionFractions containing the target compound
16. concentrationwere concentrated