Synthesis of mesoionic 3-aryl(hetaryl)-1,2,3,4-oxatriazol-5-ones based on N-aryl-and N-hetarylhydrazones of bromonitroformaldehyde

Article abstract of DOI:10.1007/BF02259369

Dehydrobromination of N-arylhydrazones of bromonitroformaldehyde (at 20°C) in the presence of alkali and ammonium salts of strong mineral acids, HNO₃, silica gel, and Al₂O₃ forms mesoionic 3-aryl-1,2,3,4-oxatriazol-5-ones