THERMODYNAMIC STUDIES OF SLOW METAL EXCHANGE PROCESSES IN IONOPHORIC CALIX[N]ARENES WITH A CAPSULE-LIKE CLOSED CAVITY

Authors
SUZUKI Y OTSUKA H IKEDA A SHINKAI S
Citation
Y. Suzuki et al., THERMODYNAMIC STUDIES OF SLOW METAL EXCHANGE PROCESSES IN IONOPHORIC CALIX[N]ARENES WITH A CAPSULE-LIKE CLOSED CAVITY, Tetrahedron letters, 38(3), 1997, pp. 421-424
Citations number
13
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Tetrahedron letters → ACNP
ISSN journal
00404039
Volume
38
Issue
3
Year of publication
1997
Pages
421 - 424
Database
ISI
SICI code
0040-4039(1997)38:3<421:TSOSME>2.0.ZU;2-R
Abstract
It was found that in a triply-capped calix[6]arene (1) and doubly-brid ged calix[8]arene (2a and 2b) with a closed ionophoric cavity the Cscomplexation occurs very slowly in a human timescale and can be follow ed by a conventional spectroscopic method. The unusual behavior has en abled us to determine their kinetic activation parameters for both the forward and the reverse reaction. The results established that being different from the concept believed so far, the Cs+ complexation is he avily governed by the entropy term but ndt by the enthalpy ten. Copyri ght (C) 1996 Elsevier Science Ltd