3,6-双(1H-1,2,3,4-四唑-5-氨基)-1,2,4,5-四嗪的合成、表征及量子化学研究

以三氨基胍硝酸盐、戊二酮为起始原料, 经缩合、氧化、取代等反应合成了3,6-双(1H-1,2,3,4-四唑-5-氨基)-1,2,4,5-四嗪(BTATz), 并通过元素分析、红外、核磁、差示扫描量热法(DSC)等分析手段对其进行了表征. 采用亚硝酸钠/乙酸代替了二氧化氮/N-甲基吡咯烷酮, 改进了氧化步骤, 降低了成本, 简化了合成工艺. 用B3LYP方法, 在6-31G(d,p)基组水平上对其性能进行了计算, 得到了其稳定的几何构型和键级; 在振动分析的基础上求得体系的振动频率、IR谱及不同温度下的热力学性质, 并得到了温度对热力学性能影响的关系式; 探讨了其热解机理, 推断出四唑环开环时的过渡态和活化能.

Synthesis, Characterization and Quantum Chemistry Study on 3,6-Bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine

3,6-Bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz) was synthesized by triamino- guanidinium nitrate with 2,4-pentanedione of condensation, followed by oxidation and substitution reaction. The product was characterized by elemental analysis, IR, NMR and DSC. Instead of nitrogen dioxide/N-methylpyrrolidone, acetic acid/sodium nitrite was as oxidizer during the oxidation, thus the cost was reduced and the process was simplified. The theoretical properties of BTATz were estimated by a B3LYP method based on 6-31G(d,p) basis set. The stable geometric configuration and bond order were obtained. The vibrational frequencies, IR spectrum and thermodynamics properties under different temperatures were obtained from vibrational analysis, and the relationship between temperature and thermodynamics properties was deducted. Pyrolysis mechanism of BTATz was discussed, and the transition state and activation energy of ring opening reaction of the tetrazole were deducted.