Synthesis and Characterization of cyclo-Pentazolate Salts of NH4+, NH3OH+, N2H5+, C(NH2)(3)(+), and N(CH3)(4)(+)
Synthesis and Characterization of cyclo-Pentazolate Salts of NH4+, NH3OH+, N2H5+, C(NH2)(3)(+), and N(CH3)(4)(+)
复制标题
NH4、NH3OH、N2H5、C(NH2)(3)( ) 和 N(CH3)(4)( ) 环五唑盐的合成和表征
DOI：
10.1021/jacs.8b05106
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发表时间：
2018
影响因子：
15
通讯作者：
Christe Karl O.
中科院分区：
文献类型：
--
作者：
Yang Chen;Zhang Chong;Zheng Zhansheng;Jiang Chao;Luo Jun;Du Yang;Hu Bingcheng;Sun Chengguo;Christe Karl O.
最近，我们在多氮化学方面取得了突破，我们大量合成了（N5）6(h30)3(NH4)4Cl，其中环五唑盐阴离子通过与NH4+和OH3+阳离子的氢桥广泛稳定。已经进行了重大的努力，以取代这些无能量的阳离子和cl阴离子更有活力的阳离子。本文报道了含简单富氮阳离子NH4+、NH3OH+、N2H5+、C(NH2)3+和N(CH3)4+的环五唑盐的合成。这些盐的特征在于它们的晶体结构；振动、质量和多核核磁共振谱；热稳定性测量；敏感数据;以及性能计算。结果表明，在80 ~ 105℃范围内，环五唑酸盐比叠氮化物具有更高的能量，但热稳定性较差。作为炸药，预测肼和羟铵盐的爆轰压力与RDX相当，但爆轰速度明显高于RDX和HMX，并具有相当的冲击和摩擦敏感性。虽然铵盐的爆轰压力低于RDX，但其爆轰速度也超过了RDX和HMX。作为火箭推进剂，预计肼和羟铵盐的性能将超过RDX和HMX。晶体结构表明，除N(CH3)4+盐也表现出很强的阳离子-π相互作用外，环五唑酸盐阴离子一般通过与阳离子的氢键稳定。这种阴离子稳定性的差异在振动谱中也可以检测到，该振动谱显示N(CH3)4+盐的环- n5−伸缩振动减少了约20 cm-1。
A breakthrough in polynitrogen chemistry was recently achieved by our bulk synthesis of (N5)6(H3O)3(NH4)4Cl in which thecyclo-pentazolate anions were stabilized extensively by hydrogen bridges with the NH4+and OH3+cations. Significant efforts have been carried out to replace these nonenergetic cations and the Cl–anion by more energetic cations. In this paper, the metathetical syntheses ofcyclo-pentazolate salts containing the simple nitrogen-rich cations NH4+, NH3OH+, N2H5+, C(NH2)3+, and N(CH3)4+are reported. These salts were characterized by their crystal structures; vibrational, mass, and multinuclear NMR spectra; thermal stability measurements; sensitivity data; and performance calculations. It is shown that thecyclo-pentazolates are more energetic than the corresponding azides but are thermally less stable decomposing in the range of 80 °C to 105 °C. As explosives, the hydrazinium and hydroxyl ammonium salts are predicted to match the detonation pressure of RDX but exhibit significantly higher detonation velocities than RDX and HMX with comparable impact and friction sensitivities. Although the ammonium salt has a lower detonation pressure than RDX, its detonation velocity also exceeds those of RDX and HMX. As a rocket propellant, the hydrazinium and hydroxyl ammonium salts are predicted to exceed the performances of RDX and HMX. The crystal structures show that thecyclo-pentazolate anions are generally stabilized by hydrogen bonds to the cations, except for the N(CH3)4+salt which also exhibits strong cation-π interactions. This difference in the anion stabilization is also detectable in the vibrational spectra which show for the N(CH3)4+salt a decrease in thecyclo-N5−stretching vibrations of about 20 cm–1.