Tetrazene, formation

The l,5-diazabicyclo[3.3.0]octane 97 was obtained, in very poor yield, by the oxidation of iV,iV-diamino-l,5-diazocine 52 through the probable intermediacy of tetrazene 96. The oxidation was performed with different reagents KjFelCN )fj in aqueous KOH HgO (red) in DCM Pb(OAc)4 in DCM. The formation of nitrogen-rich polymeric products, which might indicate intermolecular 2-tetrazene formation, was observed (Scheme 18) <1998EJO 431>. 

Hetero Diels-Alder reaction of active olefins (enamines) with triazenes, tetrazenes with loss of Nz and formation of new N-heterocycies. 

Kinetic studies. HERON reactions of 7V-acyloxy-/V-alkoxyamides, which can be conveniently followed by NMR in <74-methanol by monitoring the disappearance of the mutagen or aniline and formation of ester and tetrazene, conform to classical bimolecular kinetics being first order in both mutagen and TV-methyl-aniline.41 43,46,105 Arrhenius parameters and bimolecular rate constants (308 K) for a range of /V- a cy 1 o x y - TV- a 1 k o x y a m i de s 25-30 are collated in Table 5. 

Lead azide (PbN6) is a colorless to white crystalline explosive. It is widely used in detonators because of its high capacity for initiating secondary explosives to detonation. However, since lead azide is not particularly susceptible to initiation by impact, it is not used alone in initiator components. It is used in combination with lead styphnate and aluminum for military detonators, and is used often in a mixture with tetrazene. It is compatible with most explosives and priming mixture ingredients. Contact with copper must be avoided because it leads to formation of extremely sensitive copper azide. 

Finally, it is noteworthy that the addition of iodine azide to 3 leads mainly to the surprisingly stable tetrazido-substituted 2-tetrazene 74 (equation 76)96. The formation of 74 should start with the addition of IN3 to the double bonds of 3, giving four possible isomers. Under the applied conditions these compounds seem to be unstable. 

The reaction of aminoguanidine with sodium nitrite under neutral conditions yields tetra-zolylguanyltetrazene hydrate (85), a primary explosive commonly known as tetrazene. Tetrazene (85) is only formed in the absence of free mineral acid and so a common method for its preparation treats the bicarbonate salt of aminoguanidine (84) with one equivalent of acetic acid followed by addition of aqueous sodium nitrite. " Tetrazene (85) is decomposed by aqueous alkali to form triazonitrosoaminoguanidine (86) which is isolated as the cuprate salt (87) on addition of copper acetate to the reaction mixture. Acidification of the copper salt (87) with mineral acid leads to the formation of 5-azidotetrazole (88) (CHN7 = 88 % N).55 56... 

Formation of benzyl azide from the reaction of 1,1,4,4-tetrabenzyl-tetrazene with lead tetraacetate [70]. 

The formation of guanyl azide (IV) at the first stage may account for the formation of tetrazene by the action of nitrous acid on aminoguanidine, i.e. by Hoffmann synthesis. 

Many attempts were made to synthesize the diazaazulene derivative 4,7-diphenyl-5,6-diazaazulene 34. A directed synthesis of diazaazulene 34 by [6+4] cycloaddition of fulvenes with 1,2,4,5-tetrazenes when attempted with 2-cyclopenta-dienyliden-l,3-dioxolane led to the formation of cyclopcnta[z/ pyridazines via a [4+2] cycloaddition pathway <2001TH1>. 

Thermolysis of tetrazene 2 in cyclohexane has been reported to give the cyclic pyrrolidine and, presumably, the piperidine in 41 and 16% yields, respectively [Eq. (2)]. The formation of these reduced products must result... 

Methyl-5-(methylamino)-1 //-tctrazolc (401 R = CH3) was used as initial reagent in the synthesis of l,4-bis-[l-methyltetrazol-5-yl]-l,4-dimethyl-2-tetrazene 47, a formal hexamer of diazomethane. The synthetic pathway presumably involves intermediate formation of the corresponding nitrosotetrazole 402 and hydrazinotetrazole 405 (Scheme 48) <2004MI325>. 

The initiating reaction step of decomposition in path (a) of Eq. (56) consists of an isomerization of tran5-2-tetrazene into tra 5-l-tetrazene, which, with a-elimination of amine, produces azides [Scheme 6, Eq. (57), paths (a) and (b)]. The isomerization in path (a) [Eq. (57)] may also be the first reaction step toward transformation [Eq. (56), path (b)]. The next reaction step of trany-l-tetrazene (47), necessary for the formation of products according to Eq (56b), probably consists of an inversion according to path (c) of Eq. (57),or a dyotropic rearrangement [cf. ref. 54] as in... 

Monosubstituted tetrazene (Mc3Si)HN— N=N— NH2 is very thermo-labile (41, 42). In methylene chloride it decomposes above ca. -40 C with the formation of trimethylsilyl azide and bis(trimethylsilyl)amine, as well as ammonium azide. Thus, the (catalyzed ) decomposition of the compound follows Thermolysis Pathway IV. 

Carbon halides, CCI4 and CBr4 react with 62 in ether according to Eq. (84) with the formation of nitrogen and hydrazones (Me3Si)2N—N= CX2, as well as tetrakis(trimethylsilyl)tetrazene, trimethylsilyl halide, and... 

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