反应详情

温度

0 °C

15.5 g (0.09 mol) of 1,3-dimethyl-2-thiobarbituric acid, 8.8 g (1.1 mol) of pyridine and 0.9 g of 4-dimethylaminopyridine are dissolved in 65 ml of dichloromethane and the solution is cooled to 0° C. Then 10.2 g (0.094 mol) of ethyl chloroformate are added dropwise over 1 hours. The mixture is stirred for 12 hours at 0° C. and then for 7 hours at room temperature. The bulk of the solvent is evaporated off, a solution of 26.1 g (0.09 mol) of 4-chloro-2-(2,6-dichlorophenoxy)aniline in 360 ml of ethanol and 30 ml of dimethylformamide is added and the mixture is boiled under reflux with stirring for 6 hours. The reaction mixture is then cooled and the resultant crystalline precipitate is isolated by filtration and, if necessary, is recrystallised from dioxane/ethanol. Melting point 254°-257° C.

1. waitfor 7 hours at room temperature
2. customThe bulk of the solvent is evaporated off
3. temperatureunder reflux
4. stirringwith stirring for 6 hours
5. temperatureThe reaction mixture is then cooled
6. customthe resultant crystalline precipitate is isolated by filtration
7. customif necessary, is recrystallised from dioxane/ethanol