Zhai Lianjie, Bi Fuqiang, Huo Huan, Luo Yifen, Li Xiangzhi, Chen Sanping, Wang Bozhou
State Key Laboratory of Fluorine & Nitrogen Chemicals, Xi'an Modern Chemistry Research Institute, Xi'an, China.
College of Chemistry and Materials Science, Northwest University, Xi'an, China.
Front Chem. 2019 Aug 7;7:559. doi: 10.3389/fchem.2019.00559. eCollection 2019.
Density, detonation property, and sensitivity may be the most valued features when evaluating an energetic material. By reasoning structure-property relationships, a nitro-free planar energetic material with high nitrogen and oxygen content, 7-hydroxy-difurazano[3,4-:3',4'-]furoxano[3″,4″-]azepine (), was synthesized using a unique and facile approach. The structure was fully characterized by IR and NMR spectra, elemental analysis, differential scanning calorimetry (DSC), and single-crystal X-ray diffraction. The expected properties of , including a high density of 1.92 g cm, high detonation velocity of 8,875 m s, and low mechanical sensitivities (impact sensitivity, 21 J and friction sensitivity, >360 N), confirm our strategy. Interestingly, the single-crystal structures of reveal expected face-to-face and edge-to-face π-interactions in the crystal stacking. The remarkable differences in crystal stacking of provide unequivocal evidence that face-to-face π-π interactions contribute significantly to closer assembly and higher density.
在评估含能材料时，密度、爆轰性能和感度可能是最受重视的特性。通过推导结构-性能关系，采用独特且简便的方法合成了一种高氮氧含量的无硝基平面含能材料，即7-羟基-二呋咱并[3,4 -:3',4'-]呋咱并[3″,4″-]氮杂环庚烷（）。通过红外光谱、核磁共振光谱、元素分析、差示扫描量热法（DSC）和单晶X射线衍射对其结构进行了全面表征。的预期性能，包括1.92 g/cm的高密度、8875 m/s的高爆速以及较低的机械感度（撞击感度，21 J；摩擦感度，>360 N），证实了我们的策略。有趣的是，的单晶结构在晶体堆积中呈现出预期的面对面和边对面π相互作用。晶体堆积的显著差异提供了明确的证据，表明面对面π-π相互作用对更紧密的组装和更高的密度有显著贡献。
