反应详情

11.91 g of the cis-trans isomer mixture of 2-[3-(2-cyanoethenyl)phenyl]-[1,3]dioxolane was dissolved in 180 ml of tetrahydrofuran, and thereto 40 ml of 6 N hydrochloric acid was added dropwise under ice-cooling. After stirred at room temperature overnight, the reaction solution was concentrated under reduced pressure, and extracted with t-butyl methyl ether and then ethyl acetate. The organic layers were combined, and washed successively with an aqueous saturated sodium bicarbonate solution and then an aqueous saturated sodium chloride solution. After dried over anhydrous magnesium sulfate, crystals obtained by concentration under reduced pressured were filtered to obtain 4.90 g of trans-3-(2-cyanoethenyl)benzaldehyde [Compound No. (e)] as a white solid.

1. temperaturecooling
2. concentrationthe reaction solution was concentrated under reduced pressure
3. extractionextracted with t-butyl methyl ether
4. washwashed successively with an aqueous saturated sodium bicarbonate solution
5. dry with materialAfter dried over anhydrous magnesium sulfate, crystals
6. customobtained by concentration under reduced pressured
7. filtrationwere filtered