Molecular structure of 2-chloromethyl-1H-benzimidazole hydrochloride: Single crystal, spectral, biological studies, and DFT calculations

In the present work, structural studies on 2-chloromethyl-1H-benzimidazole hydrochloride have been performed extensively by X-ray crystallography, H-1 NMR, FT-IR, UV/vis, and elemental analysis. The title compound crystallizes in a monoclinic space group P2(1)/c with a = 7.1982 (3)angstrom, b = 9.4513(5)angstrom, c = 14.0485 (7) angstrom and beta = 102.440 (3)degrees forming an infinite chain structure parallel to b axis through the intermolecular hydrogen bond. Optimized geometrical structure, harmonic vibrational frequencies, natural bonding orbital (NBO) and frontier molecular orbitals (FMO) were obtained by DFT/B3LYP method combined with 6-31G(d) basis set. TD-DFT calculations help to assign the electronic transitions. The 1H NMR chemical shifts were computed at the B3LYP/6-311 + G(2d,p) level of theory in different solvents by applying CIAO method using the polarizable continuum model (PCM). The title compound was screened for its antibacterial activity referring to Tetracycline as a standard antibacterial agent. (C) 2011 Elsevier B.V. All rights reserved.