title: Development of functional imidazole derivatives: the influence of alkaline metal cations on the rates of CL reactions of 2-(phenyl and 4-dimethylaminophenyl)-4-hydroperoxy-4-3',4'-(15-crown-5)phenyl-5-3''-4''-(15-crown-5)phenyl-4H-isoimidazoles.
abstract: Although several investigations have focused on luminescence modulation by chelation with metal cations using bidentate ligands or crown ether systems, a bis(crown ether) system has not yet been used for modulation of chemiluminescence (CL) reactions. In the CL reaction of 2-(phenyl and 4-dimethylaminophenyl)-4-hydroperoxy-4-3',4'-(15-crown-5)phenyl-5-3'',4''(15-crown-5)phenyl-4H-isoimidazoles 2a and b possessing a bis(15-crown-5 ether) moiety, the rate acceleration was observed in the presence of K(+), Rb(+) and Cs(+) due to the holding effect of the bis-crown moiety, but no rate acceleration was observed by Li(+) and Na(+) due to the template effect of the crown moiety. The acceleration of the CL reaction rates is ascribable to the conformational change induced by the scissor-like motion of the bis-crown moiety assisted by the holding effect.
authors.affiliation: Department of Chemistry, Faculty of Science, Okayama University, Tsushima-Naka 3-1-1, Okayama 700-8530, Japan. kimuram@cc.okayama-u.ac.jp
authors.forename: Masaru
authors.initials: M
authors.lastname: Kimura
authors.forename: Kun
authors.initials: K
authors.lastname: Shi
authors.forename: Koji
authors.initials: K
authors.lastname: Hashimoto
authors.forename: Zhi Zhi
authors.initials: ZZ
authors.lastname: Hu
mesh_terms: D007093:Imidazoles / Q000737:chemistry*; D007700:Kinetics; D049449:Luminescence; D009682:Magnetic Resonance Spectroscopy; D008673:Metals, Alkaline Earth / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007093:Imidazoles; D008673:Metals, Alkaline Earth