Study on the host–guest complex of dicyclohexanocucurbit[6]uril and 2-phenylbenzimidazole, and its recognition effect toward Fe 3+

Abstract

This paper has selected dicyclohexanocucurbit[6]uril (CyH 2 Q[6]) as the host and 2-phenylbenzimidazole ( G ) as the guest to investigate the host–guest interaction mode between CyH 2 Q[6] and G . Under acidic conditions, the complex was characterized using nuclear magnetic resonance, ultraviolet and fluorescence spectroscopy. The results show that the molecular ratio of CyH 2 Q[6] to G is 2 : 1. The crystals were cultured with ZnCl 2 as a structural inducer under acidic conditions and single crystal X-ray diffraction showed that the molecular ratio of CyH 2 Q[6] to G is 1 : 3. The G@CyH 2 Q[6] was used as a fluorescent probe to identify metal cations. The probe exhibits a good selective recognition effect toward Fe 3+ ions, which involves a reduced fluorescence intensity with a limit of detection of 1.321 × 10 –6 mol l –1 .