反应详情

In 80 ml of toluene is dissolved 5.9 g of 2,4,5-trimethoxybenzaldehyde, followed by addition of 4.8 g of diethyl malonate, 0.3 ml of piperidine and 0.3 g of benzoic acid. The mixture is heated under reflux for 4 hours, water being removed via an ester tube. After cooling, the solvent is distilled off under reduced pressure and the residual crystals are recovered by filtration with n-hexane to give 8.9 g (87.3%) of diethyl 2,4,5-trimethoxybenzylidenemalonate, m.p. 86°-87° C.

1. temperatureThe mixture is heated
2. temperatureunder reflux for 4 hours
3. customwater being removed via an ester tube
4. temperatureAfter cooling
5. distillationthe solvent is distilled off under reduced pressure
6. filtrationthe residual crystals are recovered by filtration with n-hexane