Synthesis and properties of 5-nitrotetrazole derivatives as new energetic materials
作者:Thomas M. Klapötke、Carles Miró Sabaté、Matthias Rasp
DOI:10.1039/b818925k
日期:——
An improved procedure for the synthesis of ammonium 5-nitrotetrazolate (3) is given here, which allows the preparation of the material on a large scale. 3 was selectively alkylated with bromoacetonitrile yielding 5-nitrotetrazol-2-ylacetonitrile (4). The 1,3-dipolar cycloaddition of azide ion to 4 rendered 5-(5-nitrotetrazol-2-ylmethyl)tetrazole monohydrate (5a) after recrystallization from water, which was used to synthesize energetic salts with ammonium (6a), guanidinium (7) and aminoguanidinium (8) cations. The water of crystallization in the hydrated species 5a and 6a was conveniently removed under vacuum forming the anhydrous materials 5b and 6b. All compounds were characterized by analytical (elemental analysis and mass spectrometry) and spectroscopic methods (IR, Raman and NMR spectroscopy), and the crystal structures of 4 (orthorhombic, P212121, ρ = 1.747 g cm−3), 5a (monoclinic, P21, ρ = 1.796 g cm−3), 6a (triclinic, P, ρ = 1.594 g cm−3) and 8 (monoclinic, P21/n, ρ = 1.633 g cm−3) were determined by low temperature X-ray crystallography. Due to the interest in tetrazole derivatives as energetic materials, the sensitivities and energetic properties of all compounds were determined. The high detonation pressures (P) and velocities (D) of the materials (4: 29.5 GPa, 8356 m s−1, 5a: 28.7 GPa, 8341 m s−1, 5b: 30.2 GPa, 8688 m s−1, 6a: 21.3 GPa, 7658 m s−1, 6b: 22.8 GPa, 7861 m s−1, 7: 24.3 GPa, 8066 m s−1 and 8: 25.0 GPa, 8202 m s−1) make them interesting candidates to find application as environmentally friendly nitrogen-rich energetic materials.
本文给出了合成 5-硝基四唑醇铵盐 (3) 的改进程序,从而可以大规模制备这种材料。用溴乙腈对 3 进行选择性烷基化,得到 5-硝基四唑-2-基乙腈(4)。叠氮离子与 4 发生 1,3-二极环化反应,从水中重结晶后得到 5-(5-硝基四唑-2-基甲基)四唑一水合物(5a),并用它合成了含有铵(6a)、胍(7)和氨胍(8)阳离子的高能盐。水合盐 5a 和 6a 中的结晶水可在真空中轻松去除,形成无水物质 5b 和 6b。所有化合物都通过分析法(元素分析和质谱法)和光谱法(红外光谱、拉曼光谱和核磁共振光谱)进行了表征,4(正交,P212121,ρ = 1.747 g cm-3)、5a(单斜,P21,ρ = 1.796 g cm-3)、6a(三斜,P,ρ = 1.594 g cm-3)和 8(单斜,P21/n,ρ = 1.633 g cm-3)的晶体结构是通过低温 X 射线晶体学确定的。由于人们对作为高能材料的四唑衍生物很感兴趣,因此测定了所有化合物的灵敏度和高能特性。这些材料的高引爆压力(P)和速度(D)(4:29.5 GPa,8356 m s-1;5a:28.7 GPa,8341 m s-1;5b:30.2 GPa,8688 m s-1;6a:21.3 GPa,7658 m s-1;6b:22.8 GPa,7861 m s-1;6b:21.3 GPa,7658 m s-1;6a:21.3 GPa,7658 m s-1;6b:22.8 GPa,7861 m s-1。8 GPa, 7861 m s-1, 7: 24.3 GPa, 8066 m s-1 和 8: 25.0 GPa, 8202 m s-1),使它们成为环境友好型富氮高能材料的理想候选材料。