反应详情

The above aldehyde (2.25 g) was dissolved in dichloromethane (25 ml) and carboethoxymethylenetriphenylphosphorane (2.96 g) was added. After 18 hours at 25° the solution was concentrated in vacuo and the residue washed with hexane. Combined hexane washings were concentrated in vacuo to give ethyl-3-(3,4-dibromophenyl)propenoate (2.4 g). NMR 1H 7.7(2H,m), 7.50(1H,d), 7.15(1H,dd), 6.32(1H,d), 4.26(2H,q), 1.33(3H,t).

1. concentrationAfter 18 hours at 25° the solution was concentrated in vacuo
2. washthe residue washed with hexane
3. concentrationCombined hexane washings were concentrated in vacuo