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Crystal structure and properties of anhydrous 5-nitroaminotetrazole

5-Nitraminotetrazole (5-NAT) is a high-energy and green explosive material that has attracted extensive attention due to its short synthesis steps and decomposition products consisting mainly of nitrogen and water. However, the presence of a crystal water molecule in the current crystal structure of 5-nitroaminotetrazole significantly affects its detonation performance and mechanical sensitivity. In this study, we report the successful synthesis of an anhydrous crystal form of 5-NAT through slow volatilization of an ethyl acetate solution under dry conditions. The anhydrous crystal form of 5-NAT exhibited increased density and detonation velocity compared to the monohydrate crystal form. Furthermore, quantum chemical analysis showed that the anhydrous crystal form exhibited increased sensitivity to external force stimulation due to stronger oxygen-oxygen and nitrogen-oxygen repulsion. In conclusion, the anhydrous crystal form of 5-NAT shows promise as a high-energy and green primary explosive

Synthesis and Characterization of 5-Nitro-2-nitratomethyl-1,2,3,4-tetrazole: A High Nitrogen Energetic Compound with Good Oxygen Balance

The synthesis of 5-nitro-2-nitratomethyl-1,2,3,4-tetrazole (<strong>4</strong>) and its full characterization are given here. Compound <strong>4</strong> was synthesized through the nitration of 5-nitro-2-hydroxymethyl-tetrazole (<strong>3</strong>) with fuming nitric acid and acetic anhydride and its structure was characterized by MS, FT-IR, <sup>1</sup>H-NMR and <sup>13</sup>C-NMR techniques. The crystal structure of <strong>4</strong> was determined by X-ray single crystal diffraction analysis. The compound belongs to the orthorhombic system with space group <em>P</em>na2(1), and its crystal parameters were <em>a</em> <em>=</em> 2.121(8) nm, <em>b</em> <em>=</em> 0.5281(19) nm, <em>c</em> <em>=</em> 0.6246(2) nm, <em>Z</em> <em>= </em>4, <em>V </em>= 0.6995(4) nm<sup>3</sup>, <em>D</em>c = 1.805 g/cm<sup>3</sup>, <em>F</em>(000) = 384, <em>μ</em> = 0.174 mm<sup>−1</sup>. A theoretical study of <strong>4</strong> has been performed, using quantum computational density functional theory (B3LYP methods) with 6-31G* basis sets as implemented in the Gaussian 03 program suite. The obtained heat of formation (HOF) for <strong>4</strong> was 228.07 kJ·mol<sup>−1</sup>, the detonation pressure (<em>P</em>) values calculated for <strong>4</strong> was 37.92 GPa, the detonation velocity (<em>D</em>) can reach 9260 m·s<sup>−1</sup>, and the oxygen balance was zero (Q), making <strong>4</strong> a competitive energetic compound

Crystal structure and properties of anhydrous 5-nitroaminotetrazole

5-Nitraminotetrazole (5-NAT) is a high-energy and green explosive material that has attracted extensive attention due to its short synthesis steps and decomposition products consisting mainly of nitrogen and water. However, the presence of a crystal water molecule in the current crystal structure of 5-nitroaminotetrazole significantly affects its detonation performance and mechanical sensitivity. In this study, we report the successful synthesis of an anhydrous crystal form of 5-NAT through slow volatilization of an ethyl acetate solution under dry conditions. The anhydrous crystal form of 5-NAT exhibited increased density and detonation velocity compared to the monohydrate crystal form. Furthermore, quantum chemical analysis showed that the anhydrous crystal form exhibited increased sensitivity to external force stimulation due to stronger oxygen-oxygen and nitrogen-oxygen repulsion. In conclusion, the anhydrous crystal form of 5-NAT shows promise as a high-energy and green primary explosive

Boosting the Energetic Performance of Trinitromethyl-1,2,4-oxadiazole Moiety by Increasing Nitrogen-Oxygen in the Bridge

The trinitromethyl moiety is a useful group for the design and development of novel energetic compounds with high nitrogen and oxygen content. In this work, by using an improved nitration method, the dinitromethyl precursor was successfully nitrated to the trinitromethyl product (2), and its structure was thoroughly characterized by FTIR, NMR, elemental analysis, differential scanning calorimetry, and single-crystal X-ray diffraction. Compound 2 has a high density (1.897 g cm−3), high heat of formation (984.8 kJ mmol−1), and a high detonation performance (D: 9351 m s−1, P: 37.46 GPa) that may find useful applications in the field of high energy density materials

The Design, Synthesis and Application of Nitrogen Heteropolycyclic Compounds with UV Resistance Properties

Exposure to ultraviolet (UV) light is known to cause skin aging, skin damage, cancer, and eye diseases, as well as polymer material aging. Therefore, significant attention has been devoted to the research and development of UV absorbers. Considering the robust hydrogen bonding and conjugated structure present in nitrogen-containing polycyclic compounds, these compounds have been selected as potential candidates for exploring ultraviolet absorption properties. After structural optimization and the simulation of ultraviolet absorption spectra, four tris-[1,2,4]-triazolo-[1,3,5]-triazine (TTTs) derivatives, namely TTTB, TTTD, TTTJ, and TTTL, were selected as the preferred compounds and synthesized. The structure of the compound was determined using various analytical techniques, including FTIR, 1HNMR, 13CNMR, HRMS, and XRD. Subsequently, composite films of polyvinyl chloride (PVC) and TTTs were produced using a simple solvent casting technique. The PVC films were subjected to UV age testing by exposing them to an ultraviolet aging chamber. The age-resistant performance of the fabricated films was evaluated using an ultraviolet spectrophotometer and Fourier infrared spectrum instrument. The findings suggest that TTTs exhibit a noteworthy capacity for absorbing ultraviolet radiation. The TTTL compound exhibits a superior UV absorption performance compared to commercially available UV absorbers such as UV-0 and UV-327 in the market

N-Functionalization of 5-Aminotetrazoles: Balancing Energetic Performance and Molecular Stability by Introducing ADNP

5-aminotetrazole is one of the most marked high-nitrogen tetrazole compounds. However, the structural modification of 5-aminotetrazole with nitro groups often leads to dramatically decreased molecular stability, while the N-bridging functionalization does not efficiently improve the density and performance. In this paper, we report on a straightforward approach for improving the density of 5-aminotetrazole by introducing 4-amino-3,5-dinitropyrazole. The following experimental and calculated properties show that nitropyrazole functionalization competes well with energetic performance and mechanic sensitivity. All compounds were thoroughly characterized using IR and NMR spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). Two energetic compounds (DMPT-1 and DMPT-2) were further confirmed by implementing single-crystal X-ray diffraction studies. Compound DMPT-1 featured a high crystal density of 1.806 g cm−3, excellent detonation velocity (vD = 8610 m s−1), detonation pressure (P = 30.2 GPa), and impact sensitivity of 30 J

Construction of Adaptive Deformation Block: Rational Molecular Editing of the N‑Rich Host Molecule to Remove Water from the Energetic Hydrogen-Bonded Organic Frameworks

Energetic hydrogen-bonded organic frameworks (E-HOFs), as a type of energetic material, spark fresh vitality to the creation of high energy density materials (HEDMs). However, E-HOFs containing cations and anions face challenges such as reduced energy density due to the inclusion of crystal water. In this work, the modification of amino groups in N-rich organic units could form a smart building block of hydrogen-bonded frameworks capable of changing the volume of the void space in the molecule through adaptive deformation of E-MOF blocks, thus enabling the replacement of water. Based on the above strategy, we report an interesting example of a series of hydrogen-bonded organic frameworks (E-HOF 2a and 3a) synthesized using a facile method. The crystal structure data of all of the compounds were also obtained in this work. Anhydrous 2a and 3a exhibit higher density, good thermal stability, and low mechanical sensitivity. The strategy of covalent bond modification for the host molecules of energetic frameworks shows enormous potential in eliminating the crystalline H2O of hydration and exploring high energy density materials

Energetic Di- and Trinitromethylpyridines: Synthesis and Characterization

Pyridine derivatives based on the addition of trinitromethyl functional groups were synthesized by the reaction of N2O4 with the corresponding pyridinecarboxaldoximes, then they were converted into dinitromethylide hydrazinium salts. These energetic compounds were fully characterized by IR and NMR spectroscopy, elemental analysis, differential scanning calorimetry (DSC), and X-ray crystallography. These pyridine derivatives have good densities, positive enthalpies of formation, and acceptable sensitivity values. Theoretical calculations carried out using Gaussian 03 and EXPLO5 programs demonstrated good to excellent detonation velocities and pressures. Each of these compounds is superior in performance to TNT, while 2,6-bis(trinitromethyl)pyridine (D = 8700 m·s−1, P = 33.2 GPa) shows comparable detonation performance to that of RDX, but its thermal stability is too low, making it inferior to RDX