反应详情

To a solution of ethyl 2-(9H-xanthen-9-yl)-2-(3-methoxy-4-methoxycarbonylbenzoyl)acetate (7.0 g, 14.6 mmol) in dimethylsulphoxide (40 ml) was added water (0.53 ml, 29.3 mmol). The solution was stirred under an atmosphere of nitrogen at reflux for 1.5 h before cooling and diluting with water. The mixture was extracted with dichloromethane (3×) and the combined extracts washed with water (5×) and a saturated solution of sodium chloride. The organic phase was dried over magnesium sulphate, filtered and evaporated to a yellow oil. Purification on flash silica eluting with dichloromethane-hexane (3:2 then 4:1) gave a solid which was crystallised from methanol to give methyl 4-[2-(9H-xanthen-9-yl)acetyl]-2-methoxybenzoate as a yellow solid.

1. temperatureat reflux for 1.5 h
2. temperaturebefore cooling
3. extractionThe mixture was extracted with dichloromethane (3×)
4. washthe combined extracts washed with water (5×)
5. dry with materialThe organic phase was dried over magnesium sulphate
6. filtrationfiltered
7. customevaporated to a yellow oil
8. customPurification on flash silica eluting with dichloromethane-hexane (3:2
9. custom4:1) gave a solid which
10. customwas crystallised from methanol