Experimental and theoretical studies of the molecular structure of 1-(2-pyridinylmethyl)-2-methylbenzimidazole

In this work, we report a combined experimental and theoretical study on the molecular structure and vibrational spectra of 1-(2-pyridinylmethyl)-2-methylbenzimidazole. The structure of the target compound has been proposed by elemental analysis and spectroscopic data, i.e., IR, Raman, UV, MS, 1H and 13C NMR. The experimental results were supported by performing DFT calculations for the ground state geometry, electronic structure and vibrational spectra using the B3LYP functional and the 6-311+G∗∗ basis set. The optimized geometric bond lengths and bond angles obtained by using DFT have been compared with X-ray diffraction values available in the literature for the precursors (2-methylbenzimidazole and 2-picoline), as a polycrystalline structure of this compound could not be obtained in this experiment. All the experimental vibrational bands have been discussed and assigned to normal mode on the basis of our calculations. Good linear correlation between the experimental 1H and 13C NMR chemical shifts in DMSO-d6 solution and calculated GIAO shielding tensors were found.