反应详情

To a solution of 5-trimethylsilyl-2-methylphenol (Intermediate 3; 653 mg, 3.6 mmol) in THF was added potassium tert-butoxide (407 mg, 3.6 mmol) and the reaction heated at reflux for 1.5 hours. The resulting solution was allowed to cool to room temperature and concentrated under reduced pressure. The residue was taken up in dimethyl sulphoxide (10 mL), treated with methyl 5-bromo-2-furoate (632 mg, 3.1 mmol) and heated at 85° C. for 18 hours. The dark brown mixture was allowed to cool to room temperature, diluted with water (10 mL) and then acidified by the addition of hydrochloric acid (1 M). The mixture was extracted with diethyl ether (3×30 mL) and the combined organic extracts were dried (magnesium sulphate), concentrated under reduced pressure and purified by column chromatography (SiO2; light petroleum to 95:5 light petroleum-diethyl ether) to give the title compound as a colourless oil (534 mg, 57%). Rf=0.21 (9:1 light petroleum-diethyl ether). LCMS Rt=4.9 mins, m/z=305 (MH+).

1. temperaturethe reaction heated
2. temperatureat reflux for 1.5 hours
3. concentrationconcentrated under reduced pressure
4. temperatureheated at 85° C. for 18 hours
5. temperatureto cool to room temperature
6. extractionThe mixture was extracted with diethyl ether (3×30 mL)
7. dry with materialthe combined organic extracts were dried (magnesium sulphate)
8. concentrationconcentrated under reduced pressure
9. custompurified by column chromatography (SiO2; light petroleum to 95:5 light petroleum-diethyl ether)