J. Lorenc, L. Dymińska, A. F. Mohmed
Apr 20, 2007
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0
Influential Citations
4
Citations
Journal
Chemical Physics
Abstract
Abstract Molecular structure, vibrational energy levels and potential energy distribution of 1H-1,2,3-triazolo[4,5- b ]pyridine and 3H-1,2,3-triazolo[4,5- b ]pyridine as well as 1H- and 3H-tautomers of 5-methyl-1,2,3-triazolo[4,5- b ]pyridine, 6-methyl-1,2,3-triazolo[4,5- b ]pyridine and 7-methyl-1,2,3-triazolo[4,5- b ]pyridine have been determined using density functional theory (DFT) at the B3LYP/6-31G(d,p) level. In order to obtain good fitting with the experimental values the calculated frequencies have been scaled using the scaling factors 0.96 and 0.975 in the 2800–3500 and 1000–1700 cm −1 region, respectively. The role of the hydrogen bond formation in the stabilization of the structure of the studied triazolo[4,5- b ]pyridines has been discussed. The substitution place of the methyl group at the pyridine ring influences the proton position of the NH group at the triazole unit. The 5- and 7-methyl substitution leads to the 3H-tautomeric form whereas the 6-methyl substitution gives the mixture of 1H- and 3H-tautomers.