|
|||||
|
|
Stability constants of cesium complexes with 18-crown-6 in ionic liquids |
|
| Authors: | A G Vendilo H Rönkkömäki M Hannu-Kuure M Lajunen Y Asikkala A A Petrov V G Krasovsky E A Chernikova P Oksman L H J Lajunen K I Popov |
| Institution: | 1. State Research Institute of Reagents and High-Purity Substances (IREA), ul. Bogorodskii val 3, Moscow, 107258, Russia 2. Finnish Institute of Occupational Health, Chemical Agents Team, Aapistie 1, FI-90220, Oulu, Finland 3. Department of Chemistry, University of Oulu, P.O.Box 3000, FI-90014, Oulu, Finland 4. Department of Physical and Colloid Chemistry, Moscow State University of Food Technologies, Volokolamskoye Sh. 11, Moscow, Russia 5. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninskii pr. 47, Moscow, 119991, Russia |
| Abstract: | The stability constants of the complexCs(18C6)]+ (18C6 is 18-crown-6 (L)) in N-butylpyridinium methyl sulfate (I) and of the complex Cs(18C6)2]+ in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (II) were measured by using 133Cs NMR spectroscopy at 23°C. It was found that logK(Cs + L) in solvent I is 1.20±0.13 and logK(CsL + L) in solvent IIis 1.18±0.05. For the complex Cs(18C6)2]+, the dependence of its stability constant on the temperature in the 23–50°C range was obtained and the enthalpy change in the complexation was determined: ΔH(CsL + L)= ?47 kJ/mol. It was demonstrated that the enthalpy change is favorable for the formation of Cs(18C6)2]+, while the entropy change hinders the complexation. |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ | |