1-AminoTriazole Transition-Metal Complexes as Laser-Ignitable and Lead-Free Primary Explosives

This unique complex study describes two isomeric aminotriazoles as auspicious nitrogen-rich ligands for energetic coordination compounds (ECCs) to replace the commonly used highly poisonous and environmentally harmful lead-based primary explosives. The triazoles were obtained by easily scalable and convenient synthetic routes starting solely from commercially available starting materials. 1-Amino-1,2,3-triazole (1, 1-ATRI) and, for the first time, 1-amino-1,2,4-triazole (2, 1A-1,2,4-TRI) were employed as ligands to form highly energetic transition-metal(II) complexes. The desired characteristics could be altered successively by using various nonpoisonous metal(II) centers (Cu²⁺ , Mn²⁺ , Fe²⁺ , and Zn²⁺ ) and anions (Cl^- , NO₃ ^- , ClO₃ ^- , ClO₄ ^- , picrate, styphnate, 2,4,6-trinitro-3-hydroxyphenolate, and 2,4,6-trinitro-3,5-dihydroxyphenolate). The 14 synthesized coordination compounds were characterized comprehensively by XRD, IR and UV/Vis spectroscopy, elemental analysis, and differential thermal and thermogravimetric analyses. Ball-drop impact, electrostatic discharge (ESD), and mechanical (impact and friction) sensitivities were determined according to BAM standard methods. In addition to laser ignition experiments, selected ECCs were evaluated in classical secondary explosive initiation tests (detonators filled with pentaerythritol tetranitrate (nitropenta)), which revealed their enormous potential and proved them to be very attractive for future applications in explosives.