4,7-dichloro[1,2,5]oxadiazolo[3,4-d]pyridazine 1-oxide

Dihalogenated derivatives of [1,2,5]chalcogenadiazolo[3,4-d]pyridazines are of interest as precursors for both photovoltaic materials and biologically active compounds. In this communication, 4,7-dichloro[1,2,5]oxadiazolo[3,4-d]pyridazine 1-oxide was prepared via the reaction of 3,6-dichloro-5-nitropyridazin-4-amine with oxidizing agents; the best yield of the target compound was achieved in the reaction with (diacetoxyiodo)benzene in benzene by heating at reflux for two hours. The structure of the newly synthesized compound was established by means of 13C-NMR and IR spectroscopy, mass-spectrometry and elemental analysis.