Azido-tetrazole equilibrium in 2-azidothiazole system. Molecular orbital calculations

The trans–cis and the azide–tetrazole ring-chain isomerization of 2-azido-1,3-azoles: Quantum chemical study

“…2, respectively. The selected bond lengths and angles for each isomer and transition state investigated at B3LYP/6-31++G(d,p) level are given in Table 1 and 2 together with available experimental results belonging 2-azido-1,3-thiazole [34]. The relative energies, dipole moments and NBO charges of all species are shown in Table 3 and 4.…”

“…In many earlier articles, the ring-chain isomer equilibrium in the 2-azido-1,3-thiazoles has been discussed [34,35]. To our knowledge, this phenomenon in the 2-azido-1,3-imidazoles and 2-azido-1,3-oxazoles has not been studied by using computational chemistry methods yet.…”

Tetrazolium Compounds: Synthesis and Applications in Medicine

“…Compounds 11 can also be prepared in suitable yields by reaction of compounds 9 with Lawesson’s reagent or phosphorus pentoxide [ 31 ]. 1,5-Disubstituted tetrazoles can also be synthesized by reacting compounds 10 with triethyl orthoformate and sodium azide [ 32 ]. Compounds 12 can be synthesized by the reaction of compounds 10 and compounds 11 with hydrazine hydrate [ 33 , 34 ].…”

Theoretical study on the azido-cyclization of 3,6-diazido-1,2,4,5-tetrazine (DAT) with the dimethylsulfoxide (DMSO) solvent

“…So the mechanism of azido-cyclization should be known expressly and there are large numbers of experimental and theoretical studies concerning this type of isomerization. [22][23][24][25][26][27][28][29][30] A decrease of solvent polarity shifts the equilibrium towards the azide form. [31] In the gas phase, the reaction from the tetrazole to the azide is exothermic.…”