Synthesis of a Novel Benzimidazole Moiety-Appended Schiff Base Derivative: Fluorescence and Chemosensor Study

Abstract

In this study, we synthesized a novel benzimidazole-based Schiff base; (E)-4,4'-methylenebis(2-((E)-(((1H-benzo[d]imidazol-2-yl)methyl)imino)methyl)phenol) (3) was synthesized by the condensation of 5,5'-methylenebis(2-hydroxybenzaldehyde) (1) and (1H-benzo[d]imidazol-2-yl)methanamine.HCl salt (2). This Schiff base derivative was reported for the first time and fully characterized by common spectroscopic techniques. Absorption and fluorescence spectroscopy were recorded to determine the sensing ability of 3 towards metal ions. Selectivity to Zn2+ ion among studied other cations was detected. The crystal structure of 2, C<inf>8</inf>H<inf>13</inf>Cl<inf>2</inf>N<inf>3</inf>O, has been determined by single crystal X-ray diffraction method. The crystal structure of the title compound, C<inf>8</inf>H<inf>11</inf>N<inf>3</inf> 2+.2(Cl- ).H<inf>2</inf>O, consists of an organic 1H-benzoimidazol-3-ium (C<inf>8</inf>H<inf>11</inf>N<inf>3</inf> 2+ ) cation, an inorganic 2(Cl- ) anion and one water (H<inf>2</inf>O) molecule. In the cation of studied compound, C<inf>8</inf>H<inf>11</inf>N<inf>3</inf> 2+, the benzimidazole ring is almost planar with a maximum deviation of-0.012 (3) Å. The molecule crystallized in the monoclinic structure and the space group P2<inf>1</inf>/c. The crystalline stacking structure is stabilized by intramolecular N–H···Cl, N–H···O, the intermolecular N–H···Cl hydrogen bond interactions connection the molecules into a two dimensional network and between anions and the water molecules. π-π interaction between benzimidazole rings [centroid–centroid lengths = 3.4642 (2) Å, 3.5309 (2) Å and 3.5527 (2) Å] may further stabilize the structure. © 2018, Turkish Chemical Society. All rights reserved.