反应详情

温度

0 °C

4.0 g of ethyl p-[(E)-2-(4,4-dimethyl-6-chromanyl)propenyl]benzoate were dissolved in 50 ml of ether and the solution was treated slowly at 0° C. with 25.2 ml of a diisobutylaluminium hydride solution (20% in toluene). After stirring at 0° C. for 1 hour, 25 ml of methanol/water (1:1) were cautiously added dropwise thereto, the mixture was stirred at room temperature for 30 minutes and the precipitate was filtered off. The filtrate was dried, filtered over a short column of silica gel [eluting agent: hexane/ether (1:1)] and evaporated. After recrystallization from hexane/ether, there was obtained 2.9 g of p-[(E)-2-(3,4-dihydro-4,4-dimethyl-1-benzopyran-6-yl)propenyl]benzyl alcohol in the form of colorless crystals of melting point 80°-81° C.

1. stirringthe mixture was stirred at room temperature for 30 minutes
2. filtrationthe precipitate was filtered off
3. customThe filtrate was dried
4. filtrationfiltered over a short column of silica gel [eluting agent: hexane/ether (1:1)]
5. customevaporated
6. customAfter recrystallization from hexane/ether