Structure cristalline et moléculaire du benzotriazole

The synthesis and stereoelectronic structure of 1- and 2-(trimethoxysilylmethyl)- and 1- and 2-(silatranylmethyl)benzotriazole

“…1 The 1H-tautomer was found to be predominant in the solid state and solution. [9][10][11][12] According to the UV spectra of BtH, and 1-Me-and 2-Me-BtH at 90°C, there is a mixture of both BtH tautomers in an approximately 80/20 ratio. 1 The probable reason why ≈20% of the 2H-tautomer has not been detected is easy to understand, considering the corresponding dipole moments (4.2 and 0.4 D, respectively).…”

Vibrational dynamics and molecular structure of 1H- and 3H-1,2,3-triazolo[4,5-b]pyridine and its methyl-derivatives based on DFT chemical quantum calculations

“…Significant discrepancy between the experimental and theoretical data appears for the C-H bonds of the pyridine ring because the average calculated value is 1.085 Å whereas the experimental average bond length is close to 1.0 Å . Similarity of the values for the TP skeleton indicates that both the B3LYP and MPW1PW91 are good approximations for the geometry prediction of the studied compounds because the mean square deviations of the experimental and calculated values are close each other: 0.9789 for B3LYP and 0.9781 for MPW1PW91 (the geometries of the 3TP derivatives have been compared because the X-ray data are available for these tautomers [52,54]. Therefore, the geometrical data obtained from both functionals have been used in the further calculations of the vibrational wavenumbers.…”

“…The geometries of both tautomers in their energy minimum have been obtained using B3LYP and MPW1PW91/6-31G(d,p) approximations. In Table 1 all interatomic distances are compared for 1H-and 3H-tautomers of the TP and their 5-, 6-and 7-methyl derivatives together with the experimental data for BT [52] and N[(1H-1,2,3-triazolo[4,5-b] pyridin-1-yloxy) -(dimethylamino) methylene-N-methyl-methanaminium hexafluorophosphate [50,54]. The XRD and theoretical data agree very well in this point that TP skeleton is planar and some nitrogen atoms of these compounds are engaged in the intermolecular hydrogen bonds.…”

“…The structures of 1,2,3-triazolo [4,5-b]pyridine derivatives or its benzene analogues have been studied in a few works [50][51][52][53][54]. The double ring system is a basic fragment of these compounds and the experimental structural parameters could be taken from these papers for comparative purposes.…”

A theoretical study of the parent NH-benzazoles (benzimidazoles, indazoles and benzotriazoles): geometries, energies, acidity and basicity, NMR properties and molecular electrostatic potentials

“…26 The previous structures of these compounds were determined in the 1973-1974 period. 27,28 The old benzimidazole polymorph (α) is stable while the new polymorph (β) is metastable at room temperature. In both polymorphs, benzimidazole molecules are connected into polymeric chains via N-H···N hydrogen bonds (HBs).…”