反应详情

A mixture of 105.6 g of 2,4-dimethoxybenzaldehyde, 93.6 g of methyl potassium malonate, 200 ml of pyridine (dried over KOH), 1.2 ml of piperidine, 36 ml of acetic acid and 48 g of 3A molecular sieves is heated at 150° C. until evolution of CO2 has ceased. The solution is poured onto ice while hot, and the mixture is acidified to pH 1-2 with concentrated hydrochloric acid and then stirred in the ice bath for 20 minutes. The precipitate is filtered off with suction, washed with 1N HCl and water and dried.

1. additionThe solution is poured onto ice while hot, and the mixture
2. filtrationThe precipitate is filtered off with suction
3. washwashed with 1N HCl and water
4. customdried