反应详情

Ethyl 3-bromofuran-2-carboxylate (296 mg, 1.35 mmol) obtained in Step 1 of Reference Example 29, 4-(tri-n-butylstannyl)pyridine (550 mg, 1.51 mmol) and tetrakis(triphenylphosphine)palladium(0) (157 mg, 0.136 mmol) were dissolved in THF (10 mL), followed by stirring under heating and reflux for 4 hours. Aqueous ammonium fluoride solution was added to the reaction mixture, followed by extraction with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, and then the solvent was distilled away under reduced pressure. The resulting residue was purified through silica gel column chromatography (hexane:ethyl acetate=2:3) to afford ethyl 3-(4-pyridyl)furan-2-carboxylate (133 mg, 45%).

1. temperatureunder heating
2. temperaturereflux for 4 hours
3. extractionfollowed by extraction with ethyl acetate
4. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
5. distillationthe solvent was distilled away under reduced pressure
6. customThe resulting residue was purified through silica gel column chromatography (hexane:ethyl acetate=2:3)