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Anion complexation and the Hofmeister effect.

ABSTRACT: The (1)H?NMR spectroscopic analysis of the binding of the ClO4(-) anion to the hydrophobic, concave binding site of a deep-cavity cavitand is presented. The strength of association between the host and the ClO4(-) anion is controlled by both the nature and concentration of co-salts in a manner that follows the Hofmeister series. A model that partitions this trend into the competitive binding of the co-salt anion to the hydrophobic pocket of the host and counterion binding to its external carboxylate groups successfully accounts for the observed changes in ClO4(-) affinity.

SUBMITTER: Carnegie RS

PROVIDER: S-EPMC4214138 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Anion complexation and the Hofmeister effect.

Carnegie Ryan S RS Gibb Corinne L D CL Gibb Bruce C BC

Angewandte Chemie (International ed. in English) 20140905 43

The (1)H NMR spectroscopic analysis of the binding of the ClO4(-) anion to the hydrophobic, concave binding site of a deep-cavity cavitand is presented. The strength of association between the host and the ClO4(-) anion is controlled by both the nature and concentration of co-salts in a manner that follows the Hofmeister series. A model that partitions this trend into the competitive binding of the co-salt anion to the hydrophobic pocket of the host and counterion binding to its external carboxy ...[more]

PMID: 25196481

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