Crystal structure and UV spectra of a 1,2-disubstituted benzimidazolium chloride

Acta Crystallographica Section E: Crystallographic Communications

Khan, T.¹  Mhatre, D.S.¹  Datta, A.¹  Mishra, N.¹ 

[1] Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400 076, India

关键词: CRYSTAL STRUCTURE;    BENZIMIDAZOLE;    HYDROGEN BONDING;    HIRSHFELD SURFACE ANALYSIS;    DFT CALCULATIONS;    UV SPECTRA;   

DOI  :  10.1107/S205698901700977X

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

1-(2-Hy­droxy­benz­yl)-2-(2-hy­droxy­phen­yl)-1H-benzimidazol-3-ium chloride, C20H17N2O2+·Cl−, was prepared by reaction of salicyl­aldehyde with o-phenyl­enedi­amine in the presence of tri­methyl­silyl chloride acting as a source of HCl. As a result of steric hindrance, the cation in the crystal is far from planar: the benzimidazole ring system makes dihedral angles of 55.49 (9) and 81.36 (8)° with the planes of the phenolic groups. The crystal packing is dominated by O—H⋯Cl and N—H⋯Cl hydrogen bonds, which link the cations and anions into four-membered rings and then into chains along [100]. The title compound exhibits two transitions in the UV region, which are revealed in the solid state and solution spectra as an absorption maximum at 280 nm and a shoulder at 320 nm. According to the results of TD–DFT calculation, both transitions have a π–π* nature and the mol­ecular orbitals involved in these transitions are mostly localized on the benzimidazole ring system and on the phenyl ring attached to it at the 2-position.

【 授权许可】

CC BY