反应详情

To a solution of the compound obtained in the above (1) (24.7 g) in ethanol (150 mL) was added potassium carbonate (42.0 g), and the mixture was heated to reflux for 30 minutes. The reaction mixture was ice-cooled, and then acidified by 10% hydrochloric acid, and then extracted with ethyl acetate. The organic layer was washed with saturated saline, dried over sodium sulfate, and then concentrated under reduced pressure. The resulting residue was triturated with n-hexane-dichloromethane (5:1) to give ethyl 4-hydroxy-1-benzofuran-6-carboxylate [REx(7-1)] (19.6 g) as a pale yellow powder.

1. temperaturethe mixture was heated
2. temperatureto reflux for 30 minutes
3. temperaturecooled
4. extractionextracted with ethyl acetate
5. washThe organic layer was washed with saturated saline
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe resulting residue was triturated with n-hexane-dichloromethane (5:1)