1-Nitratoethyl-5-nitriminotetrazole derivatives - Shaping future high explosives

1-(2-Nitratoethyl)-5-nitriminotetrazole (2) was formed by the reaction of 1-(2-hydroxyethyl-5-aminotetrazole (1) and 100% HNO₃. Compound 1 was obtained by alkylation of 5-amino-1H-tetrazole. Next to the known byproduct 1-(2-hydroxyethyl)-5-nitriminotetrazole (3), a second one, 1-(2-nitratoethyl)-5-aminotetrazolium nitrate (4) was obtained and fully characterized. Nitrogen-rich salts such as the ammonium (5), hydroxylammonium (6), guanidinium (7), aminoguanidinium (8), diaminoguanidinium (9) and triaminoguanidinium (10) 1-(2-nitratoethyl)-5-nitriminotetrazolate were prepared by deprotonation or metathesis reactions. The reaction of 2 and diaminourea yielded 1-(2-nitratoethyl)-5-aminotetrazole (11). Compounds 4-11 were fully characterized by single crystal X-ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis and DSC measurements. The heats of formation of 5-10 were calculated by the atomization method based on CBS-4M enthalpies. Regarding the possible application of these compounds as energetic materials or high explosives, several detonation parameters such as the detonation pressure, velocity, energy and temperature were computed using the EXPLO5 code and the X-ray densities as well as the computed heats of formation. In addition the sensitivities towards impact, friction and electrical discharge were tested using the BAM drophammer, a friction tester as well as a small scale electrical discharge device.