The Dimroth rearrangement of 5-amino-1-aryl-1,2,3-triazole-4-carbothioamides

The rearrangement of 5-amino-1-aryl-1,2,3-triazole-4-carbothioamides was investigated. The process was optimized by varying the solvent, temperature, and the type of base. The optimal reaction conditions were found, and new 1-unsubstituted 5-arylamino-1,2,3-triazole-4-carbothioamides were synthesized. It has been shown that 1-aryl-1,2,3-triazoles containing a nitro group in the para position undergo rearrangement upon heating under reflux in n-butanol in the absence of a base. The rearrangement of compounds containing halogen, hydrogen, methyl, or methoxy groups in the aryl moiety requires the use of a base. The structure of the obtained compounds was confirmed by the data of NMR spectroscopy and mass spectrometry.