The combined effect of pyrazole and amino groups: preparation of novel energetic coordination compounds with high ClO₄⁻ content

The development of novel coordination compounds as energetic materials still faces significant challenges, particularly in overcoming the proportion of negative ions, which is a challenging task. Here, we prepare the ligand HDAPZCA (3,5-diamino-1H-pyrazole-4-carbohydrazide), whose skeletal ring and substituent play different roles. The coordination compound Cu(H₂DAPZCA)₂(ClO₄)₄·5H₂O (EIsCCs-1·2H2O) obtained by using it as a ligand possesses dual structural units of an ionic salt and a coordination compound. The novel structure of EIsCCs-1 endows it with a higher ClO₄⁻ content, acceptable thermal stability (T_d = 200 °C), good mechanical sensitivity (IS = 7 J, FS = 30 N), and outstanding detonation performance (D_{EXPLO 5} = 8.0 km s⁻¹, P_{EXPLO 5} = 30.9 GPa). In addition, EIsCCs-1 not only has a low energy threshold for laser initiation (E = 48 mJ) but also can be used as both a primary explosive and a secondary explosive at the same time.