Energetic alliance of tetrazole-1-oxides and 1,2,5-oxadiazolesDedicated to Dr. Klaus Römer on the occasion of his 75th birthday.Electronic supplementary information (ESI) available: X-ray diffraction data, computations, and general experimental methods. CCDC 988403-988414. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4nj01351d

The connection of highly endothermic heterocycles with high nitrogen as well as oxygen content is a recent trend in the development of new energetic materials in order to increase densities and stabilities. Bis(1-hydroxytetrazolyl)furazane ( 9 ) and bis(1-hydroxytetrazolyl)furoxane ( 10 ) were synthesized for the first time from dicyanofurazane and dicyanofuroxane, respectively. Several nitrogen-rich compounds ( e.g. ammonium and hydroxylammonium) and metal salts thereof were prepared. Most compounds were characterized by single crystal X-ray diffraction. In addition all compounds were analyzed by vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis and DSC measurements. The heats of formation of 4 , 5 , 15-16 , 20 and 24 were calculated using the atomization method based on CBS-4M enthalpies. With these values and the experimental (X-ray) densities several detonation parameters such as the detonation pressure, velocity, energy and temperature were computed using the EXPLO5 code (V.5.05). In addition, the sensitivities towards impact, friction and electrical discharge were tested using the BAM drop hammer and friction tester as well as a small scale electrical discharge device. The connection of highly endothermic heterocycles with high nitrogen as well as oxygen content is a recent trend in the development of new energetic materials in order to increase densities and stabilities.