Department of Chemistry, University of Idaho , Moscow, Idaho 83844-2343, United States.
School of Chemical Engineering, Nanjing University of Science & Technology , Nanjing 210094, China.
J Am Chem Soc. 2017 Jul 5;139(26):8816-8819. doi: 10.1021/jacs.7b05158. Epub 2017 Jun 21.
Gem-trinitromethyl groups were introduced into a 1,3,4-oxadiazole ring to give the first example of a bifunctionalized single five-membered ring with six nitro groups. 2,5-Bis(trinitromethyl)-1,3,4-oxadiazole (12) has a high calculated crystal density of 2.007 g cm at 150 K (1.941 g cm at 293 K) and a very high positive oxygen balance (39.12%), which makes it a strong candidate as a high energy dense oxidizer. The dihydroxylammonium and dihydrazinium salts of bis(trinitromethyl)-1,3,4-oxadiazole (5 and 6) exhibit excellent calculated detonation properties (5, v = 9266 m s, P = 38.9 GPa; 6, v = 8900 m s, P = 36.3 GPa) and acceptable impact sensitivities (5 20 J, 6 19 J), which are superior to those of RDX (7.4 J) and HMX (7.4 J). Such attractive features support the application potential of the gem-polynitromethyl group in the design of advanced energetic materials. Surprisingly, 2,5-bis(trinitromethyl)-1,3,4-oxadiazole (12) is more thermally stable and less sensitive than its bis(dinitromethyl) analogue, 8.
三硝甲基取代 1,3,4-噁二唑环生成首例双官能化单五元环六硝化合物。2,5-双(三硝甲基)-1,3,4-噁二唑(12)在 150 K 时具有高理论密度 2.007 g cm(-3)(293 K 时为 1.941 g cm(-3))和极高的正氧平衡值(39.12%)，使其成为高能密度氧化剂的有力候选物。双(三硝甲基)-1,3,4-噁二唑的二羟胺盐和二肼盐表现出极好的理论爆轰性能(5，v = 9266 m s(-1)，P = 38.9 GPa；6，v = 8900 m s(-1)，P = 36.3 GPa)和可接受的撞击感度(5，20 J；6，19 J)，优于 RDX(7.4 J)和 HMX(7.4 J)。这些吸引人的特性支持了偕多硝甲基基团在先进含能材料设计中的应用潜力。令人惊讶的是，2,5-双(三硝甲基)-1,3,4-噁二唑(12)比其偕二硝甲基类似物 8 更热稳定，感度更低。
