Insight into structural and energetic features of substituted triazolofurazans

Abstract

A comparative study of experimentally established structures, stability and energetic performance for ammonium and hydrazinium salts of 4H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole (triazolofurazan, TF) as well as its N-oxide and N-nitroimide was performed. The aim of this study was to reveal the structure-property relationships of heterocyclic systems by the example of triazolofurazan derivatives. It was shown, that the introduction of N-oxide oxygen into position 5 of the TF anion led to a small loss in enthalpy of formation (4 kcal·mol–1) while introduction of the N–NO2 (N-nitroimido) group in the same position added a significant amount of energy into the molecule (36 kcal·mol–1). Both substituents improved oxygen balance and increased the density (0.065–0.22 g·cm-3) of the final salts however only N-oxide enhanced the thermal stability by ca. 35–45 °C while N-nitroimide either retained unchanged or decreased heat resistance compared to unsubstituted analogues.