Synthesis and crystal structure of the first amino-1,3a,4,6a-tetraazapentalenes

Synthesis of the first amino- and formylamino-1,3a,4,6a-tetraazapentalenes via thermolysis of the corresponding 4-amino- and 4-formylamino-2-(2-azidophenyl)-2H-[1,2,3]-triazoles has been elaborated. The crystal structures of 2-amino-3-(tert-butyl-NNO-azoxy)-1H-[1,2,3]triazolo[2,1-a][1,2,3]benzotriazol-1-id-4-ium and 3-amino-2-(tert-butyl-NNO-azoxy)-1H-[1,2,3]triazolo[2,1-a][1,2,3]benzotriazol-1-id-4-ium have been established using X-ray diffraction analysis.