Energetic High-Nitrogen Compounds: 5-(Trinitromethyl)-2H-tetrazole and -tetrazolates, Preparation, Characterization, and Conversion into 5-(Dinitromethyl)tetrazoles

Abstract

A convenient access to 5-(trinitromethyl)-2H-tetrazole (HTNTz) has been developed, based on the exhaustive nitration of 1H-tetrazole-5-acetic acid, which was prepared from ethyl cyanoacetate and HN3 in a 1,3-dipolar cycloaddition reaction, followed by basic hydrolysis. HTNTz was converted into the ammonium, guanidinium, rubidium, cesium, copper, and silver 5-(trinitromethyl)-2H-tetrazolates. In addition, the ammonia adducts of the copper and silver salts were isolated. The reaction of HTNTz with hydrazine and hydroxylamine resulted in the formation of hydrazinium 5-(dinitromethyl)tetrazolate and hydroxylammonium 5-(dinitromethyl)-1H-tetrazolate, respectively. Acid treatment of both 5-(dinitromethyl)tetrazolates resulted in the isolation of 5-(dinitromethylene)-4,5-dihydro-1H-tetrazole, which was converted into potassium 5-(dinitromethyl)-1H-tetrazolate by reaction with K2CO3. All prepared compounds were fully characterized by (1)H, (13)C, (14)N, and (15)N NMR spectroscopy and X-ray crystal structure determination. Initial safety testing (impact, friction, and electrostatic sensitivity) and thermal stability measurements (differential thermal analysis, DTA) were also carried out. The 5-(trinitromethyl) and 5-(dinitromethyl)tetrazoles are highly energetic materials that explode upon impact or heating.

Energized nitro-substituted azoles through ether bridges

“…As can be seen, the ether bridge is also bonded at the 2-position of the tetrazole (N1) ring, which is comparable to the hydrogen atom bonded to the same position in the parent compound. 11 The bond lengths and angles of the 5-trinitromethyltetrazolyl moiety are similar to those in the literature. Compound 4 crystallizes in the monoclinic space group P2 1 /c with a calculated density of 1.789 g cm -3 at 100 K. The structure is shown in Figure 3.…”

“…Bis(chloromethyl)ether, 9 5-trinitromethyltetrazole, 11 sodium 5nitrotetrazole, 16 4-choro-3,5-dinitropyrazole, 4b 4-amino-3,5dinitropyrazole, 4b 3,5-dinitro-1,2,4-triazole, 17 3-ntiro-1,2,4triazole, 18 3,4-dinitropyrazole, 19 3,5-dinitropyrazole 20 Impact and friction sensitivity measurements were made using a standard BAM Fallhammer and a BAM friction tester. Densities were determined at room temperature by employing a Micromeritics AccuPyc 1330 gas pycnometer.…”

“…Compound 1 crystallizes in the triclinic space group P-1 with two molecular moieties in each unit cell. In comparison to the parent compound, 5trinitromethyltetrazole (d = 1.918 g cm -3 ), 1 has a density of 1.910 g cm -3 at 100 K. 11 The high density is rationalized by the hydrogenbonded network and the O---O interactions ( Figure 2). As can be seen, the ether bridge is also bonded at the 2-position of the tetrazole (N1) ring, which is comparable to the hydrogen atom bonded to the same position in the parent compound.…”

5-(Fluorodinitromethyl)-2H-tetrazole and its tetrazolates – Preparation and Characterization of New High Energy Compounds

“…5,29 Due to the compound's reported sensitivity and high reactivity, trinitroacetonitrile was recommended to be handled only in solution. 27 As a result, trinitroacetonitrile had not been fully characterized.…”

“…While energetic, tetrazoles are usually notoriously under-oxidized. 5-Nitrotetrazolate 12 has an OB of 14.0% for combustion to CO but the recently investigated 5-(trinitromethyl)tetrazolate 5 has an OB of 29.4%. The general disadvantage of most 5-(trinitromethyl)tetrazolates are their high impact (IS) and friction sensitivities (FS) (e.g.…”