A Family of Energetic Materials Based on 1,2,4-Oxadiazole and 1,2,5-Oxadiazole Backbones With Low Insensitivity and Good Detonation Performance

Qi Xue; Fu-Qiang Bi; Jun-Lin Zhang; Zi-Jun Wang; Lian-Jie Zhai; Huan Huo; Bo-Zhou Wang; Sheng-Yong Zhang

doi:10.3389/fchem.2019.00942

A Family of Energetic Materials Based on 1,2,4-Oxadiazole and 1,2,5-Oxadiazole Backbones With Low Insensitivity and Good Detonation Performance

Front Chem. 2020 Feb 20:7:942. doi: 10.3389/fchem.2019.00942. eCollection 2019.

Authors

Qi Xue¹, Fu-Qiang Bi¹, Jun-Lin Zhang¹, Zi-Jun Wang^{1

2}, Lian-Jie Zhai^{1

2}, Huan Huo¹, Bo-Zhou Wang¹, Sheng-Yong Zhang^{1

3}

Affiliations

¹ State Key Laboratory of Fluorine & Nitrogen Chemicals, Xi'an Modern Chemistry Research Institute, Xi'an, China.
² Department of Chemistry, Technische Universität München, Garching bei München, Germany.
³ Department of Medicinal Chemistry, Fourth Military Medical University, Xi'an, China.

Abstract

Design and synthesis of new compounds with both high detonation performances and good safety properties have always been a formidable task in the field of energetic materials. By introducing -ONO₂ and -NHNO₂ moieties into 1,2,4-oxadiazole- and 1,2,5-oxadiazole-based backbones, a new family of energetic materials, including ammonium 3-nitramino-4-(5-hydroxymethyl-1,2,4-oxadiazol-3-yl)-furazan (4), 3,3'-bis[5-nitroxymethyl-1,2,4-oxadiazol-3-yl]-4,4'-azofuroxan (6), [3-(4-nitroamino-1,2,5-oxadiazol-3-yl)-1,2,4-oxadiazol-5-yl]-methylene nitrate (8), and its energetic ionic salts (10-12), were synthesized and fully characterized. The energetic and physical properties of the materials were investigated through theoretical calculations and experimental determination. The results show that the oxadiazole-based compounds exhibit high enthalpy of formations, good detonation performances, and extraordinary insensitivities. In particular, the hydrazinium salt (11) shows the best energetic properties (11: d = 1.821 g cm^-3; P = 35.1 GPa, v _D = 8,822 m s^-1, IS = 40 J, FS > 360N). The ESP and Hirshfeld surface analysis indicated that a large number of hydrogen bonds as well as π-π stacking interactions within molecules might be the key reason for their low sensitivities and high energy-density levels.

Keywords: 1,2,4-oxadiazole; crystal structure; detonation performances; energetic materials; synthesis.