Abstract The room temperature ionic liquid 1??n??butyl??3??methylimmidazolium tetrafluoroborate ([bmim] BF4) was used to promote the synthesis of 5??arylidene barbituric acids and thiobarbituric acid derivatives under the solid??state conditions of grinding or microwave irradiation without organic solvent. The yields were 77.9–96.2%. It is shown that the proposed method is fast, efficient, and environmentally benign.
![5-[(3-nitrophenyl)methylidene]-2-sulfanylidene-1,3-diazinane-4,6-dione Structure](https://image.chemsrc.com/caspic/216/60045-64-9.png)