Nitrogen‐Rich Salts Based on the Energetic 5,5′‐(Hydrazine‐1,2‐diyl)bis[1H‐tetrazolide] Anion

Abstract

The reaction of 5,5'-(hydrazine-1,2-diyl)bis[1H-tetrazole] (HBT) with N-bases yielded a new family of energetic N-rich salts based on the 5,5'-(hydrazine-1,2-diyl)bis[1H-tetrazol-1-ide] anion with ammonium (see 1), hydrazinium (see 2), guanidinium (see 3), and aminoguanidinium (see 4) cations (5,5'-(hydrazine-1,2-diyl)bis[1H-tetrazol-1-ide] ¼ 5,5'-(hydrazine-1,2-diyl)bis[tetrazolate]). All compounds were characterized by analytical and spectroscopic methods, and the crystal structure of 1 was determined by X-ray analysis (triclinic, P1 ). (Carboxyamino)guanidine betaine monohydrate (¼ 2-(aminoiminomethyl)hydrazinecarboxylic acid hydrate (1 : 1); 5) was obtained as a by-product in the synthesis of 4 and was characterized by X-ray analysis (monoclinic, P2 1 /c). Differential-scanning calorimetric (DSC) measurements were used to assess the thermal behavior of the energetic salts 1 -4, and bomb calorimetry allowed us to determine the experimental constant-volume energies of formation ðD c U exp Þ. In addition, the detonation parameters (pressure and velocity) were calculated from the energies of formation (back-calculated from D c U exp ) with the EXPLO5 code, and their validity was checked by comparison with the results obtained from theoretical constant-volume energies of formation ðD c U pred Þ obtained by means of quantum-chemical calculation (MP2) of electronic energies and an approximation of lattice enthalpy. Lastly, the sensitivity to shock, friction, and electrostatic discharge of 1 -4 was measured by submitting the compounds to standard tests, and the ICT code was used to predict the products formed upon decomposition of the salts.

Imidazol‐2‐ylidene Reactivity towards Cyanocarbons

“…The N–C–C–N dihedral angle between the two ring systems varies between 9.4–10.9° such that some degree of conjugation may exist between the tetrazolide and imidazolium moieties. The geometric parameters for the imidazolium5c,10a–10f and tetrazolide8,11a–11e groups are in good agreement to other examples reported herein (and elsewhere). Interestingly, the structure of 20 contains five water molecules of solvation that encase the tetrazolide group in a ring of “ice”.…”

New Takes on Nitrate Ester Chemistry: Salts with Oxygen‐Rich Ammonium Cations

“…The DG r (298) values calculated for nitrate salts with nonquaternary ammonium cations are generally consistent with the hypothesized correlation between thermal stability and computed DG r (298) values. Relatively large negative DG r (298) values for the nitrates salts of ammonium (15), methylammonium (16), N,N-dimethylammonium (17), and N,N,N-trimethylammonium (18) nitrate were obtained, and all have DSC decomposition onsets @ 150 C. The only other salts in the table with a primary, secondary, or tertiary ammonium group and a negative DG r (298) value are trizma (14) nitrate (CAS# 41521-38-4) and 2-nitroxyethylammonium (7) nitrate. 2-Nitroxyethylammonium (7) nitrate has been observed to react violently when raised to 75 8C, but we could not find reports of its behavior at room temperature.…”

“…New materials have been created from a wide variety of platforms, with charge delocalized, asymmetric cations paired with oxygen rich nitrate, dinitramide, perchlorate, 3-nitro-1,2,4-triazol-5-one, nitroformate, 3,5-dinitro-1,2,4-triazolate, and even nitrotetrazole N-oxide anions being among those synthesized [1][2][3][4][5][6][7][8][9][10]. Most efforts have focused on designing and constructing cations with aza-heterocycles because they tend to have high densities, stabilizing charge delocalization, endothermic properties, and resistance to oxidation [11][12][13][14][15][16][17][18][19][20]. However, the electrophillic nature of most oxygen-rich functional groups makes the creation of oxygen-rich materials difficult.…”

The crystal structure of (1E,2E)‐2,2′‐dipyridylglyoxime

“…We are interested in the synthesis, characterization, and properties of nitrogen-rich compounds [1,2], metal complexes with nitrogen bases [3][4][5], and reactions with nitrogen-based substrates [6][7][8]. In this context, dioximes have recently been described by Croitor and coworkers [9] as mediators for the synthesis of Cd II and Zn II complexes, which exhibit luminescence properties.…”