Snyder Christopher J, Chavez David E, Imler Gregory H, Byrd Edward F C, Leonard Philip W, Parrish Damon A
Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
Naval Research Laboratory, Washington, DC, 20375, USA.
Chemistry. 2017 Nov 21;23(65):16466-16471. doi: 10.1002/chem.201704394. Epub 2017 Oct 30.
The reaction of 3,4-dinitropyrazole, 5-nitrotetrazole, or 4-nitro-1,2,3-triazole with 1,2,4,5-tetrazines substituted with 3,5-dimethylpyrazolyl (dmp) groups results in energetic cocrystals after 1 minute of reflux and cooling to room temperature in yields of 89-92 %. Hydrogen-bonding between the dmp group to the N-H of the energetic heterocycles are the predominant interaction that stabilizes the new cocrystals. Each cocrystal packs in a different lattice structure and the cocrystals with sheet-like and herring-bone crystal packing orientations are less sensitive than the cocrystal with the interlocked structure. Electrostatic potential mapping helps rationalize why dmp-substituted tetrazines readily form cocrystals, whereas more electron-deficient pyrazolyl tetrazines do not. The calculated energetic performance of the new cocrystals approaches that of 2,4,6-trinitrotoluene (TNT) and importantly, these materials will aid in the rational design of new cocrystalline energetic materials.
3,4-二硝基吡唑、5-硝基四唑或4-硝基-1,2,3-三唑与3,5-二甲基吡唑基（dmp）取代的1,2,4,5-四嗪反应，回流1分钟并冷却至室温后，可得到能量型共晶体，产率为89 - 92%。dmp基团与含能杂环的N - H之间的氢键是稳定新共晶体的主要相互作用。每种共晶体以不同的晶格结构堆积，具有片状和人字形晶体堆积取向的共晶体比具有互锁结构的共晶体更不敏感。静电势映射有助于解释为什么dmp取代的四嗪容易形成共晶体，而电子缺乏程度更高的吡唑基四嗪则不然。新共晶体的计算能量性能接近2,4,6-三硝基甲苯（TNT），重要的是，这些材料将有助于合理设计新型共晶含能材料。
