The nitration of 5-aminotetrazole

Abstract

The similarity between 5-aminotetrazole and guanidine in certain structural features suggested that nitraminotetrazole might be prepared from 5-aminotetrazole much as nitroguanidine can be prepared from guanidine. 5-Aminotetrazole has generally been looked upon as an acidic substance since it was first described by Thiele (1). Although the amino group can be acylated (2) and under suitable conditions diazotized (1), its salts with mineral acids are extensively hydrolyzed in aqueous solution.5-Aminotetrazole nitrate (3) can be prepared by crystallization of 5-aminotetrazole from warm, moderately concentrated nitric acid. Presumably the amino group is involved in salt formation, although participation of the ring nitrogens cannot be excluded. Dehydration of the nitrate with sulfuric acid at room temperature led \ j|.he formation of a nitraminotetrazole. Analogy with the guanidine series suggested that 5-nitroaminotetrazole (I) would be formed but structures such as l-nitro-5-aminotetrazole (II) or 2-nitro-5-aminotetrazole

Nitration Products of 5‐Amino‐1H‐tetrazole and Methyl‐5‐amino‐1H‐tetrazoles – Structures and Properties of Promising Energetic Materials

“…In the chiral space group P2 1 2 1 2 1 , the Friedel pairs were merged. Selected data from the X-ray data collection and refinements are given in Compound 2 was characterized as a dibasic acid with pK a values of 2.5 and 6.1 [15]; previously it was not possible to locate the H-atoms, and it was assumed that the more acidic H-atom is located at the nitramino group [25]. However, using single crystaldiffraction both H-atoms were located on the tetrazole ring at N(1) and N(4).…”

“…However, there are two main methods. The first synthesis involves protonation of 5-amino-1H-tetrazole (5-AT, 1) [13] using warm concentrated HNO 3 , to form 5-amino-1H-tetrazolium nitrate [14], followed by dehydration with concentrated H 2 SO 4 [15] to form 2. Another synthetic route is based on the cyclization of nitroguanyl azide [16] [17] (also known as (nitroazido)formamidine).…”

Energetic Oxygen‐Containing Tetrazole Salts Based on 3,4‐Diaminotriazole

“…Compound 1 and the oxygen-containing tetrazoles were synthesized according to procedures reported in the literature. [41,[56][57][58][59] 3,4-Diamino-1,2,4-triazole (2)…”

Energetic salts based on 1-amino-1,2,3-triazole and 3-methyl-1-amino-1,2,3-triazole

“…As shown in Scheme 2, compounds 2 and 5 were prepared by treating 1-amino-1,2,3-triazole with nitric acid and nitroform (d), respectively. Given that 5-nitro-tetrazole (b) and 5-nitroiminotetrazole (c) (Scheme 1) are strong acids (c was characterized as a dibasic acid with pK a values of 2.5 and 6.1), 29 they can easily protonate ATZ and form energetic nitrogen rich salts. We also attempted to synthesize salt 6 by anion exchange between 1amino-1,2,3-triazolium sulfate and barium azotetrazolate or anion exchange between 1-amino-1,2,3-triazolium hydrochloride and silver azotetrazolate, but no desired product was formed possibly because barium azotetrazolate or silver azotetrazolate decomposes in acidic media.…”