反应详情

温度

120 °C

To a mixture of ethyl veratroylacetate (45 g) and urea (11.7 g) were added conc. hydrochloric acid (5 drops) and ethanol (5 ml). The mixture was heated at 120° C. for 16 hours under reduced pressure. To the residue was added another conc. hydrochloric acid (5 drops) and ethanol (5 ml) and the mixture was heated again at 150° C. for 2 hours under reduced pressure. The resulting residue was washed successively with ethyl acetate, ethanol and isopropyl ether to give 6-(3,4-dimethoxyphenyl)-2,4(1H,3H)-pyrimidinedione (12.2 g).

1. temperaturethe mixture was heated again at 150° C. for 2 hours under reduced pressure
2. washThe resulting residue was washed successively with ethyl acetate, ethanol and isopropyl ether