反应详情

6,8-Bis-(4-hydroxy-butyl)-3-(4-methoxy-phenyl)-chromen-2-one (14.3 g, 36.0 mmol) is dissolved in 270 ml dichloromethane and a solution of boron tribromide (12 ml, 126 mmol) in 30 ml dichloromethane is added under ice-cooling. The cooling is removed and the reaction mixture is stirred overnight at room temp. The solution is poured onto ice/water, acidified with 2 N hydrochloric acid, and extracted three times with ethyl acetate. The combined organic layers are washed with water and dried over sodium sulfate. The solvent is removed in vacuo and the residue is filtered through silica gel with toluene/THF (7:3). 6,8-Bis-(4-hydroxy-butyl)-3-(4-hydroxy-phenyl)-chromen-2-one is obtained as a viscous oil.

1. temperaturecooling
2. customThe cooling is removed
3. additionThe solution is poured onto ice/water
4. extractionextracted three times with ethyl acetate
5. washThe combined organic layers are washed with water
6. dry with materialdried over sodium sulfate
7. customThe solvent is removed in vacuo
8. filtrationthe residue is filtered through silica gel with toluene/THF (7:3)