反应详情

To 110 g of the resulting 1,3-dimethylbarbituric acid was added 32 ml of water, and 800 ml of phosphorus oxychloride was slowly added dropwise thereto. After heating at reflux for 1.5 hours, the phosphorus oxychloride was removed by distillation at normal pressure. The residue, while hot, was poured onto ice, and the thus formed crystals were collected by filtration. The filtrate was extracted three times with chloroform and dried over anhydrous sodium sulfate, followed by distillation to remove chloroform. The residue was combined with the above obtained crystals. Recrystallization from water gave 80 g (64%) of 6-chloro-1,3-dimethyluracil having a melting point of 113° to 115° C.

1. additionwas slowly added dropwise
2. temperatureAfter heating
3. temperatureat reflux for 1.5 hours
4. customthe phosphorus oxychloride was removed by distillation at normal pressure
5. additionThe residue, while hot, was poured onto ice
6. filtrationthe thus formed crystals were collected by filtration
7. extractionThe filtrate was extracted three times with chloroform
8. dry with materialdried over anhydrous sodium sulfate
9. distillationfollowed by distillation
10. customto remove chloroform
11. customabove obtained crystals
12. customRecrystallization from water