N-bound primary nitramines based on 1,5-diaminotetrazole.

1,5-Diaminotetrazole can be nitrated under very mild conditions by using nitronium tetrafluoroborate to result in 5-amino-1-nitriminotetrazole (1) in good yields. The same reaction can be performed with 1-amino-5-amino-4-methyltetrazole to yield 5-amino-4-methyl-1-nitriminotetrazole (2). Both compounds have been isolated and completely characterized by using vibrational spectroscopy, mass spectrometry, and differential scanning calorimetry. Additionally, X-ray diffraction measurements of the neutral compounds could be obtained; they indicated the structure of both compounds to be zwitterionic. Compounds 1 and 2 exhibit extremely high sensitivities to impact and friction and high positive heats of formation of 496 (1) and 453 kJ mol(-1) (2), respectively. Additionally, high-nitrogen-containing salts of 1 have been synthesized by metathesis reactions of silver 5-amino-1-nitriminotetrazolate with the corresponding halides so as to investigate the changes in sensitivity and thermal stability. All ionic compounds have been synthesized in good yields and characterized by means of vibrational and multinuclear NMR spectroscopy as well as X-ray diffraction measurements. Thermal stabilities have been evaluated by differential scanning calorimetry, whereas sensitivity measurements have been performed according to standardized Bundesanstalt für Materialforschung und -prüfung (BAM) tests. Theoretical calculations have been performed to investigate the heats of formation as well as the performance characteristics of the compounds.

Energetic salts of the binary 5-cyanotetrazolate anion ([C2N5]-) with nitrogen-rich cations.

The reaction of cyanogen (NC-CN) with MN(3) (M=Na, K) in liquid SO(2) leads to the formation of the 5-cyanotetrazolate anion as the monohemihydrate sodium (1·1.5 H(2)O) and potassium (2) salts, respectively. Both 1·1.5 H(2)O and 2 were used as starting materials for the synthesis of a new family of nitrogen-rich salts containing the 5-cyanotetrazolate anion and nitrogen-rich cations, namely ammonium (3), hydrazinium (4), semicarbazidium (5), guanidinium (6), aminoguanidinium (7), diaminoguanidinium (8), and triaminoguanidinium (9). Compounds 1-9 were synthesised in good yields and characterised by using analytical and spectroscopic methods. In addition, the crystal structures of 1·1.5 H(2)O, 2, 3, 5, 6, and 9·H(2)O were determined by using low-temperature single-crystal X-ray diffraction. An insight into the hydrogen bonding in the solid state is described in terms of graph-set analysis. Differential scanning calorimetry and sensitivity tests were used to assess the thermal stability and sensitivity against impact and friction of the materials, respectively. For the assessment of the energetic character of the nitrogen-rich salts 3-9, quantum chemical methods were used to determine the constant volume energies of combustion, and these values were used to calculate the detonation velocity and pressure of the salts using the EXPLO5 computer code. Additionally, the performances of formulations of the new compounds with ammonium nitrate and ammonium dinitramide were also predicted. Lastly, the ICT code was used to determine the gases and heats of explosion released upon decomposition of the 5-cyanotetrazolate salts.

Synthesis and characterization of 4,5-dicyano-2H-1,2,3-triazole and its sodium, ammonium, and guanidinium salts.

In this contribution, the synthesis and structural characterization of the 4,5-dicyano-1,2,3-triazolate anion in its sodium, ammonium, guanidinium, aminoguanidinium, diaminoguanidinium, and triaminoguanidinium salts is reported. The synthesis of 4,5-dicyano-2H-triazole (1) was repeated as described in the literature (Johansson, P. et al. Solid State Ionics 2003, 156, 129) and spectroscopically characterized using (1)H, (13)C, and (15)N NMR, IR, and Raman spectroscopy, as well as differential scanning calorimetry (DSC) and mass spectrometry (DEI+). The molecular structure was determined for the first time using X-ray diffraction (1: monoclinic, P2(1)/c, a = 6.0162(6) A, b = 11.2171(10) A, c = 7.5625(7) A, beta = 94.214(8) degrees, V = 508.97(8) A(3), Z = 4). Compound 1 was deprotonated using Na(2)CO(3) to form the corresponding sodium salt of the 4,5-dicyano-1,2,3-triazolate anion (2) as a monohydrate. This compound was also characterized using (13)C, (14)N, (15)N NMR, IR, and Raman spectroscopy, as well as single crystal X-ray diffraction (2: monoclinic, P2(1)/c, a = 3.6767(6) A, b = 20.469(4) A, c = 9.6223(13) A, beta = 97.355(13) degrees, V = 718.2(2) A(3), Z = 4). Reaction of 2 with AgNO(3) yielded silver 4,5-dicyano-1,2,3-triazolate (3) which was characterized using IR and Raman spectroscopy, as well as DSC, and was used to prepare the ammonium (4), guanidinium (5), aminoguanidinium (6), diaminoguanidinium (7), and triaminoguanidinium (8) salts of the 4,5-dicyano-1,2,3-triazolate anion in a metathetical reaction from the corresponding ammonium and guanidinium halides. All new compounds (4-8) were spectroscopically characterized ((1)H and (13)C NMR, IR, Raman), the stabilities investigated using DSC, the mass spectra obtained using the FAB+ and FAB- methods and the solid state structures determined using single crystal X-ray diffraction: (4): orthorhombic, Pnma, a = 6.5646(13) A, b = 7.5707(16) A, c = 13.303(3) A, V = 661.1(2) A(3), Z = 4; (5): monoclinic, Cc, a = 12.6000(11) A, b = 17.1138(15) A, c = 12.0952(9) A, beta = 106.098(7) degrees, V = 2505.9(4) A(3), Z = 12; (6): monoclinic, Pa, a = 7.0921(9) A, b = 7.2893(9) A, c = 8.8671(11) A, beta = 105.141(11) degrees, V = 442.48(10) A(3), Z = 2; (7): monoclinic, P2(1), a = 3.7727(4) A, b = 15.6832(17) A, c = 8.3416(10) A, beta = 101.797(10) degrees, V = 483.13(9) A(3), Z = 2; (8): monoclinic, C2/c, a = 14.0789(14) A, b = 11.5790(11) A, c = 13.5840(14) A, beta = 115.239(10) degrees, V = 2003.1(3) A(3), Z = 8. The impact and friction sensitivities of compounds 4-8 were investigated using drop hammer and friction apparatus methods, and all compounds were found to be neither impact (> 30 J) nor friction sensitive (> 360 N). The detonation parameters of compounds 5- 8 were computed using the EXPLO5 code.

New azidotetrazoles: structurally interesting and extremely sensitive.

The treatment of triaminoguanidinium chloride with two equivalents of sodium nitrite under acidic conditions, followed by the cyclization with stoichiometric amounts of either sodium hydroxide solution or solid sodium carbonate yielded 1-amino-5-azidotetrazole (1), 5-azido-1-diazidocarbamoyltetrazole (2), and 1-(aminoazidocarbamoyl)-5-azidotetrazole (3). The three novel compounds could be isolated by short-column liquid chromatography by using chloroform in reasonable yields. The mechanism of the formation as well as the decomposition pathway of the materials was investigated and a full characterization of all three compounds is presented. Compounds 1-3 have been characterized by means of Raman and IR as well as multinuclear NMR spectroscopy, mass spectrometry, and X-ray diffraction studies. Thermal stabilities have been evaluated by differential scanning calorimetry. Theoretical calculations have been performed to ensure the assignment of the vibrational modes obtained from Raman and IR measurements. The sensitivity values obtained from our measurements reflect the behavior of the compounds, which show an extremely high sensitivity toward mechanical as well as thermal stimuli.