A novel One-Pot Synthesis of 4-Substituted-1,2,4-triazolidine-3,5-diones

A simple and one-pot pathway for the preparation of 4-substituted phenyl derivatives of triazolidindiones (urazoles), ­starting from aniline derivatives is reported. In these methods aniline derivatives were reacted with ethyl chloroformate, to give the corresponding carbamate derivatives. In the second step ­semicarbazide derivatives were prepared from these carbamates by reaction with ethyl carbazide. The cyclization reactions of the corresponding semicarbazides furnished triazolidindiones. All reactions were performed in one vessel without the isolation of reaction intermediates, such as carbamates and semicarbazides, and the final products were isolated in good yields.