Silver salt of 5-nitrotetrazole

The silver(I) salt of tetrazole, Ag(tta), was mentioned by Bladin in 1892 (25) more recently, silver(I) tetrazolates Ag(5-R-tta) have been obtained from silver nitrate and the free tetrazole or 5-substituted tetrazole (78, 94,134). The silver salt of 5-nitrotetrazole, Ag(5-02N-tta),... 

Silver salt of 5-nitrotetrazole is known to exist in six polymorphic forms which is the major disadvantage of this compound [4], whereas the mercuric salt does not exhibit polymorphism [54]. The very wide range of crystal structures of Hg(NT>2 has been reported [4]. The big drawback of mercury 5-nitrotetrazole is its incompatibility with aluminum [42]. 

Compatibility of the silver salt of 5-nitrotetrazole has been investigated by Blay and Rapley [55]. They exposed a thin layer of AgNT on a metal surface at 50-60 °C to humid conditions for up to 8 weeks. They observed that it is incompatible with aluminum, the metal being corroded at humidity levels as low as 75% (significantly more than for SA). Copper and brass were less affected, and only at 100% relative humidity, and no corrosion of stainless steel was observed under the conditions of the test. The silver salt of 5-nitrotetrazole is compatible with HMX, RDX, and the lead salt of dinitroresorcine. However, when a mixture of AgNT with tetrazene was stored at high humidity, both tetrazene and AgNT rapidly decomposed, but a similar mixture stored at low humidity showed no decomposition. The silver salt of 5-nitrotetrazole is more resistant to rubbers and plastics than SA. Spectrophoto-metric determination of the silver salt of 5-nitrotetrazole has also been published by Blay and Rapley [55]. 

Thermal stability of AgNT has been studied by Blay and Rapley [55]. Temperature of ignition is 262 °C at a heating rate of 5 °C min. The silver salt of 5-nitrotetrazole is thermally less stable than S A. TypicaUy, a 20% mass loss occurs within 3 h at240 °C (compared with 3% for SA) [55]. 

Silver and mercury salts of 5-nitrotetrazole were also investigated as possible replacements for LA and at the end of the investigation, it was concluded that MNT is very effective in small detonators with a superior performance than LA... 

Metallic salts are mostly soluble in water (e.g., alkaline, salts of alkaline earths, cadmium, and thallium). The silver, mercury, cobalt, and nickel salts are insoluble in cold water cobalt and cupric salts give a dihydrate [4]. Nitrotetrazole salts have good chemical stability and are not sensitive to carbon dioxide nor influenced by moisture. They may be stored without deterioration in hot and humid climates [1]. The cupric salt of 5-nitrotetrazole is not hygroscopic [48]. The crystals of this salt are shown in Fig. 8.2. 

Other metallic salts of 5-nitrotetrazole (e.g., silver) are prepared by treating aqueous solutions of NaNT, [Cu(en)2](NT)2, or [Cu(pn)2](NT)2 with the soluble version of the relevant metallic salt [4,41,42,46,47,53,54,59,65,67]. In the case of [Cu(en)2](NT)2 or [Cu(pn)2](NT)2 diamine must first be broken down and destroyed or made inactive to prevent complex formation with the metal. This is easily achieved by reaction with nitric acid (to tie up the diamine) followed by addition of the mercuric nitrate solution (mercuric salt forms) [4, 42, 46, 56, 66]. The several methods of Hg(NT)2 analysis are summarized in [67]. 

Alkyl derivatives of 5-nitrotetrazole form by alkylation of the metallic salts of 5-nitrotetrazole (e.g., sodium, silver) by alkyUialogenide [4]. 

Aminotetrazole (91) reacts with potassium permanganate in excess aqueous sodium hydroxide to yield the disodium salt of 5-azotetrazole (92). 5-Azotetrazole is unstable and attempts to isolate it by acidification yields 5-hydrazinotetrazole (93). Diazotization of 5-aminotetrazole (91) in the presence of excess sodium nitrite yields 5-nitrotetrazole (94), a powerful explosive whose mercury and silver salts are primary explosives. ... 

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