title: Competitive cesium-133 NMR spectroscopic study of complexation of different metal ions with dibenzo-21-crown-7 in acetonitrile-dimethylsulfoxide and nitromethane-dimethylsulfoxide mixtures.
abstract: (133)Cs NMR spectroscopy was used to determine the stoichiometry and stability of the Cs(+) ion complex with dibenzo-21-crown-7 (DB21C7) in acetonitrile-dimethylsulfoxide (96.5:3.5, w/w) and nitromethane-dimethylsulfoxide (96.5:3.5, w/w) mixtures. A competitive (133)Cs NMR technique was also employed to probe the complexation of Na(+), K(+), Rb(+), Ag(+), Tl(+), NH(4)(+), Mg(2+), Ba(2+), Hg(2+), Pb(2+) and UO(2)(2+) ions with DB21C7 in the same solvent systems. All the resulting 1:1 complexes in nitromethane-dimethylsulfoxide were more stable than those in acetonitrile-dimethylsulfoxide solution. In both solvent systems, the stability of the resulting complexes was found to vary in the order Rb(+)>K(+) approximately Ba(2+)>Tl(+)>Cs(+)>NH(4)(+) approximately Pb(2+)>Ag(+)>UO(2)(2+)>Hg(2+)>Mg(2+)>Na(+).
authors: Department of Chemistry, Razi University, Kermanshah, Iran. mshamsipur@yahoo.com
authors: Mojtaba
authors: M
authors: Sahmsipur
authors: Leila Shafiee
authors: LS
authors: Dastjerdi
authors: Nader
authors: N
authors: Alizadeh
authors: Hamid Reza
authors: HR
authors: Bijanzadeh
mesh_terms: D000097:Acetonitriles / Q000737:chemistry*; D002586:Cesium / Q000737:chemistry*; D047248:Crown Compounds / Q000737:chemistry*; D043844:Crown Ethers / Q000737:chemistry*; D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D009595:Nitroparaffins / Q000737:chemistry*
chemical_list: D000097:Acetonitriles; D047248:Crown Compounds; D043844:Crown Ethers; D009595:Nitroparaffins; C529668:dibenzo-21-crown-7; D002586:Cesium; D008697:Methane; C008640:nitromethane; D004121:Dimethyl Sulfoxide; C032159:acetonitrile