Location of a metallic cation complexed in a calixarene cavity as determined by calixarene 13C spin relaxation. application to cesium and thallium complexed by p-sulfonatocalix[4]arene in water.
J Phys Chem B
; 113(11): 3499-503, 2009 Mar 19.
Article
en En
| MEDLINE
| ID: mdl-19239218
ABSTRACT
This study deals with the exact location of the monovalent metal cations Cs(+) and Tl(+) which are complexed by the p-sulfonatocalix[4]arene in water. This determination rests on the measurements of longitudinal relaxation times of carbon-13 not directly bonded to protons. The difference between the relaxation times of the free calixarene and of the complex definitely demonstrates that the monovalent metal cation is well inside the calixarene cavity. These features are in fact enhanced by the presence of paramagnetic species which act in a different way in the complexed form. Experimental results also show without any ambiguity that the calixarene cavity is essentially hydrophobic. Finally, it is observed that thallium is more mobile than cesium within the calixarene cavity.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fenoles
/
Talio
/
Cationes
/
Cesio
/
Calixarenos
/
Metales
Idioma:
En
Revista:
J Phys Chem B
Asunto de la revista:
QUIMICA
Año:
2009
Tipo del documento:
Article
País de afiliación:
Francia