A Candidate of New Insensitive High Explosive; MTNI

1-methyl-2,4,5-trinitroimidazole (MTNI; 1) was reinvestigated and fully characterized as a promising candidate of new insensitive high explosives. Compound 1 was synthesized from the imidazole (2), via 5 step reactions. According to our preliminary sensitivity tests, 1 was almost as insensitive as TNT. The explosive performances, i.e. detonation velocity, and C-J pressure, were evaluated theoretically, and were found to be comparable to those of RDX. In addition, owing to its low melting point, 82 C, we believe that 1 is an excellent candidate of melt-castable explosives. The structure of 1 was characterized by X-ray diffraction. The crystal is orthorhombic; M = 434.23, Pca21, a = 8.6183(6) Å, b = 17.7119(12) Å, c = 10.6873(7) Å, Z = 4, V = 1631.38(19) Å, Dc = 1.768 g/cm. The structure was refined to R = 0.0278 for 3474 independent reflections with I > 4σ(I). The molecular structures calculated by high levels of ab initio and density functional theories were in good agreement with that observed by X-ray experiment.