7477-13-6Relevant articles and documents
Dual Reactivity of 1,2,3,4-Tetrazole: Manganese-Catalyzed Click Reaction and Denitrogenative Annulation
Chattopadhyay, Buddhadeb,Das, Sandip Kumar,Khatua, Hillol,Roy, Satyajit
supporting information, p. 304 - 312 (2020/10/29)
A general catalytic method using a Mn-porphyrin-based catalytic system is reported that enables two different reactions (click reaction and denitrogenative annulation) and affords two different classes of nitrogen heterocycles, 1,5-disubstituted 1,2,3-triazoles (with a pyridyl motif) and 1,2,4-triazolo-pyridines. Mechanistic investigations suggest that although the click reaction likely proceeds through an ionic mechanism, which is different from the traditional click reaction, the denitrogenative annulation reaction likely proceeds via an electrophilic metallonitrene intermediate rather than a metalloradical intermediate. Collectively, this method is highly efficient and offers several advantages over other methods. For example, this method excludes a multi-step synthesis of the N-heterocyclic molecules described and produces only environmentally benign N2 gas a by-product.
NMR studies of the equilibria produced by 6- and 8-substituted tetrazolo [1,5-a] pyridines
Cmoch, Piotr,Stefaniak, Lech,Webb, Graham A.
, p. 237 - 242 (2007/10/03)
1H, 13C and 15N NMR data are reported for nine tetrazoles. Five of these compounds are found to exhibit valence tautomeric equilibrium between the tetrazole and azide forms. The position of this equilibrium at 298 K is found to be dependent on the solvent and the position and nature of the substituent. More polar solvents favour the tetrazole form. Protonation studies on the two forms using TFA as a solvent are reported. The favoured site of protonation is found to be N-4 for the azide form and N-1 for the tetrazole form.
