反应详情

To a solution of 4-[1-(4-bromo-2-ethylphenyl)methylidene]-2,5-diethyl-2,5-dimethyldihydrofuran-3-one (20 g, 0.055 mol) in methanol (800 ml) is added a solution of 50% aqueous hydrogen peroxide (9.58 ml, 0.165 mol) and a solution of 2N aqueous sodium hydroxide (10.98 ml, 0.02 mol) at ambient temperature. The reaction mixture is stirred at ambient temperature for 12-15 hours. The reaction mixture is quenched with a solution of saturated aqueous sodium metabisulfite, evaporated under reduced pressure to remove most of the solvent and extracted with dichloromethane (3×100 ml). The organic phases are combined, washed with water, and dried over anhydrous sodium sulfate. The mixture is filtered, and the filtrate is evaporated under reduced pressure to give 2-(4-bromo-2-ethylphenyl)-4,6-diethyl-4,6-dimethyl-1,5-dioxaspiro[2.4]heptan-7-one (15 g), used without further purification in the next step.

1. customat ambient temperature
2. customThe reaction mixture is quenched with a solution of saturated aqueous sodium metabisulfite
3. customevaporated under reduced pressure
4. customto remove most of the solvent
5. extractionextracted with dichloromethane (3×100 ml)
6. washwashed with water
7. dry with materialdried over anhydrous sodium sulfate
8. filtrationThe mixture is filtered
9. customthe filtrate is evaporated under reduced pressure