反应详情

温度

-78 °C

Methyl (7-methoxybenzofuran-3-yl)acetate (12.37 g) was dissolved in dichloromethane (50 ml) and the solution was cooled to −78° C. To this solution, boron tribromide (1.0 M, 120 ml) was added dropwise for 50 minutes. Thereafter, the temperature was raised to room temperature and the reaction solution was stirred at this temperature for 3 hours. After completion of the reaction, the reaction solution was cooled to −78° C. and methanol (100 ml) was added thereto. After neutralizing the reaction mixture by adding sodium hydrogen carbonate, the resulting solution was filtered. The filtrate was concentrated and poured into water layer (300 ml) and the resultant was extracted twice with ether (150 ml). After combining the organic layers, the resultant was washed with saturated brine and dried over sodium sulfate. After removing the sodium sulfate by filtration, the solvent was removed under reduced pressure and the residue was purified by column chromatography (solvent: hexane/ethyl acetate=2/1) using silica gel to obtain the desired compound (10.53 g, yield: 91%).

1. temperatureThereafter, the temperature was raised to room temperature
2. customAfter completion of the reaction
3. temperaturethe reaction solution was cooled to −78° C.
4. filtrationthe resulting solution was filtered
5. concentrationThe filtrate was concentrated
6. additionpoured into water layer (300 ml)
7. extractionthe resultant was extracted twice with ether (150 ml)
8. washthe resultant was washed with saturated brine
9. dry with materialdried over sodium sulfate
10. customAfter removing the sodium sulfate
11. filtrationby filtration
12. customthe solvent was removed under reduced pressure
13. customthe residue was purified by column chromatography (solvent: hexane/ethyl acetate=2/1)