Synthesis of gem-Dinitromethylated and Fluorodinitromethylated Derivatives of 5,5'-Dinitro-bis-1,2,4-triazole as Promising High-Energy-Density Materials.

gem-Dinitromethylated and fluorodinitromethylated 5,5'-dinitro-3,3'-bis-1,2,4-triazole (DNBT) (2 and 3) along with seven ionic derivatives 4-9, were synthesized and characterized by NMR and IR spectroscopies, elemental analysis, single-crystal X-ray diffraction (XRD), and differential scanning calorimetry (DSC). XRD revealed that compounds 2 and 3 crystallized in the monoclinic P2 /n space group and compound 5 crystallized in the monoclinic P2 /c space group. The physicochemical properties of the as-synthesized compounds 2-9 were investigated and the results indicated that compounds 3, 6, and 7 exhibited a good balance between high energy and low sensitivity, demonstrating their potential as new high-energy-density materials (HEDMs). The proposed synthetic strategy for introducing gem-dinitromethyl and fluorodinitromethyl groups into the DNBT framework to prepare materials with high energy and low sensitivity suitable for HEDMs looks promising.