Maximum Compaction of Ionic Organic Explosives: Bis(hydroxylammonium) 5,5′‐Dinitromethyl‐3,3′‐bis(1,2,4‐oxadiazolate) and its Derivatives

Abstract

Within this contribution on bis(oxadiazoles) we report on bis-hydroxylammonium 5,5'-dinitro-methyl-3,3'-bis(1,2,4-oxadiazolate), which (to the best of our knowledge) shows the highest density (2.00 g cm(-3) at 92 K, 1.95 g cm(-3) at RT) ever reported for an ionic CHNO explosive. Also the corresponding bis(ammonium) salt shows an outstanding density of 1.95 g cm(-3) (173 K). The reaction of the 3,3'-bis(1,2,4-oxadiazolyl)-5,5'-bis(2,2'-dinitro)-diacetic acid diethyl ester with different nitrogen-rich bases, such as ammonia, hydrazine, hydroxylamine, and triaminoguanidine causes decarboxylation followed by the formation of the corresponding salts (cation/anion stoichiometry 2:1). The reactions are performed at ambient temperature in H2O/MeOH mixtures and furnish qualitatively pure products showing characteristics of typical secondary explosives. The obtained compounds were characterized by multinuclear NMR spectroscopy, IR and Raman spectroscopy, as well as mass spectrometry. Single-crystal X-ray diffraction studies were performed and the structures of all compounds were determined at low temperatures. The thermal stability was measured by differential scanning calorimetry (DSC). The sensitivities were explored by using the BAM drophammer and friction test. The heats of formation were calculated by the atomization method based on CBS-4M enthalpies. With these values and the X-ray densities, several detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code.

A new family of energetic salts based on oxy-bridged bis(dinitromethyl)furazan: syntheses, characterization and properties

“…In contrast to the previously reported 5,5'-dinitromethyl-3,3'-bis (1,2,4-oxadiazole) anion, 11 the dinitromethyl groups and furazan rings on the same side of the bridged oxygen atom are clearly twisted rather than nearly planar, which contribute to the lower density than that of 5,5'-dinitromethyl-3,3'-bis(1,2,4-oxadiazole) based salts. In contrast to the previously reported 5,5'-dinitromethyl-3,3'-bis (1,2,4-oxadiazole) anion, 11 the dinitromethyl groups and furazan rings on the same side of the bridged oxygen atom are clearly twisted rather than nearly planar, which contribute to the lower density than that of 5,5'-dinitromethyl-3,3'-bis(1,2,4-oxadiazole) based salts.…”

Synthesis and crystal structure of trinuclear potassium(I) complex with oxy-bridged bis(gem-dinitro)furazan and triaminoguanidinium

“…And these two protons with a ratio of 1:2, indicating the TAG + cation was existed in the compound 2. Furthermore, in 13 C NMR spectra (Fig. 1b), three signals at 161.1, 142.7 and 119.0 ppm can attribute to O-C=N-, -N=CC(NO 2 ) 2 and C(NO 2 ) 2 of the OBNF 2-anion, which are close to the reported data [21].…”

“…It was noted that the 13 C NMR signal of gem-dinitro group carbon (C(NO 2 )) at 119.0 ppm appeared at higher field compared to the ones in literature (129 to 132 ppm) [22][23][24], which resulted from the conjugation of negative charge throughout the aromatic rings [21]. 1 H NMR (a) and 13 C NMR (b) spectra for the potassium(I) complex in DMSO ) cation, three potassium cation As to the anion, the bridged oxygen atom is nearly C5-N6 he dihedral angle between two furazan ring planes (defined by C2C3N4O5N3 and C5C4N5O7N6) between two furazan ring planes is 33.48 o , while one (defined by C8C9N11O16N12 and C10C11N13O18N14) is only 14.48 o , which are similar to the reported oxy-bridged furazan structures [15]. The length of the C-C bonds (C2-C3, C4-C5, C8-C9 and C10-C11) connecting gem-dinitro and furazan ring are 1.420, 1.426, 1.420 and 1.422 Å, respectively.…”

“…In this regard, compounds such as, nitramine or tetrazole-functionalized based furazan had been investigated and were found to have shown promising performance [7][8][9][10][11][12]. The gem-dinitro group has been reported as being an effective anion to construct gem-dinitro group containing energetic compounds, with the high value of density contribution of 1.759 g cm -3 [13][14][15]. To the best of our knowledge, the way of introducing gem-dinitro group into furazan ring to construct energetic compound is an effective strategy for developing novel energy material.…”

Electrostatic Potentials, Intralattice Attractive Forces and Crystal Densities of Nitrogen-Rich C,H,N,O Salts

“…The next most positive ion in Table 1 is the ammonium ion, NH 4 + , which has four hydrogen maxima of 181 kcal/mol, but they are separated by distinctly less positive regions ( Figure 5). We have surveyed 87 nitrogen-rich C,H,N,O salts that have been synthesized during the past five years [16,30,[34][35][36][37][38][39][40][41][42][43][44][45][46]. (Only anhydrous salts were considered.)…”