Assembly of 1D Helical Energetic Coordination Polymers Using a Flexible Bridged Furazan-triazole Cation

Two new energetic coordination compounds with 1D helical chain structures have been synthesized. First, the polyamine precursor 4,5-diamino-2-((4-amino-1,2,5-oxadiazole-3-yl)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-imino chloride salt (TATAF-Cl) is obtained by incorporating 4-(chloromethyl)-1,2,5-oxadiazol-3-amine with 4H-1,2,4-triazole-3,4,5-triamine. Using a simple hydrothermal method, two energetic complexes, Ag(TATAF)(ClO₄)₂ (ECP-1) and Ag(TATAF)(NO₃)₂·H₂O (ECP-2), with a helical 1D MOF structure of furazan and triazole were synthesized. Compounds ECP-1 and ECP-2 have relatively high nitrogen and oxygen content (N + O%: 52.04%, 61.04%), excellent crystal density (2.229 g cm^-3, 2.116 g cm^-3 at 298 K) and high heat of detonation (1.18 kcal g^-1, 1.06 kcal g^-1), good detonation performance (P: 35.34 GPa, 29.52 GPa; D_v: 8412 m s^-1, 7794 m s^-1), and moderate sensitivity (IS: 8 J, 13 J; FS: 72 N, 64 N). Structurally, the Ag⁺ of the two ECPs is coordinated with two energetic cations, two perchlorates, or one nitrate via tetragonal coordination to form a single helical structure that is interspersed up and down in two directions.