Taming of 5-(Nitramino)-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole

A common approach to the design of new high-energy compounds is the selection of a framework that defines the main parameters of the future molecule, followed by fine-tuning by the introduction of substituents, primarily explosophores. Currently, the most popular strategy for framework design involves its assembly by combining several heterocyclic rings (e.g., furazanes, furoxanes, triazoles, tetrazoles, tetrazines), allowing the advantages of each of them to be utilized in the final molecule. Fine-tuning of such scaffolds is usually achieved by the introduction of explophoric substituents such as N-oxides, N-NO2, C(NO2)2, etc. [1,2,3]Triazolo[4,5-c][1,2,5]oxadiazole (triazolo-furazan, TF) is an interesting framework for the construction of novel high-energy systems because it consists of two strong energy-consuming nuclei (1,2,3-triazole and furazan) with a large number of N-N and C-N bonds. In addition to the fact that such an annulated 5+5 system is poorly studied, the introduction of an explozophoric N-NO2 fragment into its structure has not been addressed before us in the literature. The objectives of the present thesis work were the synthesis of ammonium and hydrazinium (NH4+ and N2H5+) salts of 5-(nitramino)-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole (NIATO) and the study of their physicochemical and special properties. We were able to develop an original strategy for the synthesis of ammonium and hydrazinium salts of 5-(nitramino)-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole based on diaminofurazan. A key step in this synthetic route is an intramolecular thermal cyclization previously unknown in the furazane series, involving azido and bis(2-cyanoethyl)triazene groups. Using this strategy, new types of salts containing the Y-aromatic tripoidal fragment N4 were obtained. An alternative route involved an intramolecular oxidation reaction of aminotriazenylfurazane. A comparative study of the ammonium and hydrazinium salts of triazolofurazane, its N-oxide and N-nitroimide was also carried out to investigate the relationship between experimentally determined structures, stability and energetic characteristics. The introduction of the N-NO2 group at position 5 of the TF anion improves the oxygen balance, imparts a significant amount of energy (36 kcal-mol-1) to the molecule and increases the density by 0.22 g-cm -3. The thermal stability either remains unchanged or decreases. The triazolofurazan nucleus was shown to be a high-energy and relatively strong scaffold, which allows it to be used for the preparation of new energetic compounds.