反应详情

温度

0 °C

Sodium methoxide (5.08 g, 0.094 mol) is added to a solution of 2,5-diethyl-2,5-dimethyldihydrofuran-3-one (8 g, 0.047 mol) in dimethoxyethane (40 ml) at 0° C. The reaction mixture is stirred for 15 minutes at 0° C. and a solution of 4-bromo-2-ethyl benzaldehyde (8.96 g, 0.042 mol) in dimethoxyethane (8 ml) is added. The reaction mixture is stirred at 0° C. for 1 hour, acidified to pH 1 with 2N aqueous hydrochloric acid and extracted with diethyl ether (3×75 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 4-[1-(4-bromo-2-ethylphenyl)methylidene]-2,5-diethyl-2,5-dimethyldihydrofuran-3-one (17 g), used without further purification in the next step.

1. stirringThe reaction mixture is stirred at 0° C. for 1 hour
2. extractionextracted with diethyl ether (3×75 ml)
3. washwashed with water
4. dry with materialdried over anhydrous sodium sulfate
5. filtrationThe mixture is filtered
6. customthe filtrate is evaporated under reduced pressure