Aminotetrazoles structure

Mercuric-5-nitrotetrazole [Structure (2.13)] was prepared according to the methods reported by Gilligan et al. [14] and Redman and Spear [15]. Thus, 5-aminotetrazole was treated with sodium nitrite and copper sulfate to obtain Cu(NT)2HNT-4H20 (where NT nitrotetrazole). The copper salt was subsequently converted to the ethylene diamine complex MNT was then obtained by treating the complex with mercuric nitrate in HN03 medium. The precursors and final product were air dried. The synthesis of these compounds is carried out in a fume hood behind a protective polycarbonate shield in a stainless steel reaction vessel. 

Beil (Ref 1) this compd was not prepd in the free state but its prepn by Rathsburg (Ref 4) by oxidg amino tetr azole in ale sol ns with permanganate or persulfates is described in CA 17, 1147(1923). A diazotetrazole was prepd by diazotizing aminotetrazole The British abstract of the patent of Rathsburg (Ref 4) shows an azotetrazole with the structure ... 

Fig. 2. 3 Structures of silver nitraminotetrazolate and disilver(aminotetrazole) perchlorate.

Fig. 2.10 Molecular structures of triaminoguanidinium azotetrazolate (TAGzT) and hydrazinium 5-aminotetrazolate (HyAt).

Diazotetrazole (16) was obtained by dropwise addition of 2-pentyl nitrite to a solution of 5-amino-l//-tetrazole in a 4 1 mixture of tetrahydrofuran and aqueous hydrochloric acid. The diazonium chloride can be extracted into ether. Shevlin obtained the extremely explosive solid diazonium salt (16) by evaporation of that solution. He has recommended that not more than 0.75 mmol of diazonium salt be isolated at one time. An explosion during the diazotization of 5-aminotetrazole on a laboratory scale was described by Gray and coworkers. The structure 17 (equation 5) indicates clearly that this diazo compound may have the tendency to decompose into atomic carbon and three equivalents of dinitrogen—a reaction which is clearly highly exothermic. The decomposition of the tetrazole-5-diazonium chloride (16) has been studied by Shevlin by coating the salt on the walls of a 500 ml flask in the presence of two substrates, ethene and ethylene oxide. With ethene the products found after heating the flask to 80 °C are shown in equation 6, and with ethylene oxide in equation 7. The products correspond to those found with atomic carbon formed by completely different methods (see references cited by Shevlin). 

Dialkyl(alkyl-A/-1H-tetrazol-5-ylalkan(or benzenecarbox)imidato)-boron compounds of type 29 have been prepared from 5-aminotetrazole, nitriles, R CN, and trialkylboranes, R3B, by heating the stirred mixture (containing an excess of R CN) to 120°C [20, 21]. The derivatives are characterized by mass spectral, IR, and UV data. An X-ray structure analysis was performed on 29f. The bicyclic skeleton of this compound is almost planar with some distortion about the boron atom [20]. 

The nomenclature of nitroaminotetrazoles (also referred to as nitramino-or nitriminotetrazoles) is usually inconsistent in literature [52] as a result of incomplete characterization of the previously reported compounds. Therefore, a complete characterization of three well-known nitroaminotetrazoles is given in this chapter (see also [53]). The crystal structures show the first examples of neutral 5-aminotetrazoles that have been nitrated at the primary NH2 group. For 5-nitroaminotetrazole only the cell parameters have been previously pubhshed [54], while several examples of 5-methyl-nitraminotetrazoles have been structurally characterized and reported in the literature [55]. On the basis of the crystal structures obtained, the nitration product of 5-aminotetrazole (1) is now referred to as 5-nitriminotetrazole (2). 

Aminotetrazole 197 contains a structurally implemented guanidine moiety that has been apphed by Cai et al. in the multicomponent synthesis of dihydrotetrazolopyrimidines 198 [83],... 

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