Xia Honglei, Jiang Tianyu, Qi Guangyu, Liu Tianlin, Zhang Wenquan, Zhang Qinghua
Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621999, China.
School of Astronautics, Northwestern Polytechnic University, Xi'an 710072, China.
Inorg Chem. 2024 Jul 22;63(29):13166-13170. doi: 10.1021/acs.inorgchem.4c01050. Epub 2024 Jul 8.
Pentazole (-HN) is a unique heterocycle categorized as both an organic and inorganic compound. However, attempts to synthesize and characterize -HN have been unsuccessful thus far. In this study, we synthesized a -HN solution and investigated the spectra, structure, aromaticity, acidity, and stability of -HN. The lone pair of electrons on the protonated N atom of -HN participates in π-electron delocalization, forming two N═N bonds. Further investigations suggest that -HN exhibits significantly decreased π aromaticity and slightly lower σ aromaticity than -N. Experimental results suggest that pure -HN is unstable at ambient temperatures and pressures, but it can be isolated at high pressures or stabilized in solution by abundant hydrogen bonds. The p of -HN was determined as 1.63 (HO, 25 °C) via potentiometric titration, indicating that -HN is a medium-strong acid. This study reveals the fundamental structure and properties of -HN, thereby providing important data for advancing -HN chemistry.
戊唑（-HN）是一种独特的杂环化合物，既被归类为有机化合物，也被归类为无机化合物。然而，迄今为止，合成和表征-HN的尝试均未成功。在本研究中，我们合成了一种-HN溶液，并研究了-HN的光谱、结构、芳香性、酸度和稳定性。-HN质子化氮原子上的孤对电子参与π电子离域，形成两个N═N键。进一步的研究表明，与-N相比，-HN的π芳香性显著降低，σ芳香性略低。实验结果表明，纯-HN在常温常压下不稳定，但在高压下可以分离出来，或者通过大量氢键在溶液中稳定存在。通过电位滴定法测定-HN的p为1.63（HO，25°C），表明-HN是一种中强酸。本研究揭示了-HN的基本结构和性质，从而为推进-HN化学提供了重要数据。
