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Self-assembled ionophores, formed by hydrogen bonding of isoG 1 around a ca
tion, are dynamic structures. Multinuclear NMR spectroscopy in CD3CN-CDCl3
showed that cation exchange is >10(4) faster than exchange of isoG 1 ligand
in (isoG 1)(10)-Cs+ Ph4B-. The cationic guest also affected the kinetic st
ability of the complex. 2D-EXSY NMR experiments in CDCl3 showed that ligand
exchange was 2 orders of magnitude faster for the Li+-decamer than for the
Cs+-decamer.