An Efficient One-Step Reaction for the Preparation of Advanced Fused Bistetrazole-Based Primary Explosives

The first example of [5,6,5]-tricyclic bistetrazole-fused
energetic
materials has been obtained through a one-step reaction from commercial
and inexpensive 4,6-dichloro-5-nitropyrimidine. This one-step reaction
including nucleophilic substitution, nucleophilic addition, cyclization,
and electron transfer is rarely reported, and the reaction mechanism
and scope is well investigated. Among target compounds, organic salts
exhibit higher detonation velocities (D: 8898–9077
m s–1) and lower sensitivities (IS: 16–20
J) than traditional high energy explosive RDX (D =
8795 m s–1; IS = 7.5 J). In addition, the potassium
salt of 5-azido-10-nitro-bis­(tetrazolo)­[1,5-c:5′,1′-f]­pyrimidin
(DTAT-K) possesses excellent priming ability, comparable
to traditional primary explosive Pb­(N3)2, and
ultralow minimum primary charge (MPC = 10 mg), which is the lowest
MPC among the reported potassium-based primary explosives. The simple
synthesis route, free of heavy metal and expensive raw materials,
makes it promising to quickly realize this material in large-scale
industrial production as a green primary explosive. This work accelerates
the upgrade of green primary explosives and enriches future prospects
for the design of energetic materials.

[5,6,5]-三环双四唑并含能材料的首例化合物可由商用廉价的4,6-二氯-5-硝基嘧啶经一步反应制得。该一步反应涵盖亲核取代、亲核加成、环化与电子转移过程，此类反应鲜有报道，其反应机制与适用范围已得到充分研究。在目标化合物中，有机盐的爆速（D：8898–9077 m·s⁻¹）与感度（IS：16–20 J）均优于传统高能炸药黑索金（RDX，D=8795 m·s⁻¹；IS=7.5 J）。此外，5-叠氮基-10-硝基双(四唑并)[1,5-c:5′,1′-f]嘧啶的钾盐（DTAT-K）具备优异的起爆能力，可与传统起爆药叠氮化铅（Pb(N₃)₂）相媲美，且其最小起爆药量（MPC=10 mg）极低，为已报道的钾基起爆药中最低值。该合成路线简便，无需使用重金属与昂贵原料，有望作为绿色起爆药快速实现大规模工业化生产。本研究推动了绿色起爆药的迭代升级，也为含能材料的设计研发拓展了新的前景。