Complex formation of alkali chlorides with benzo-18-crown-6 incorporated in poly(vinyl alcohol) in water + dioxane and water + tetrahydrofuran mixtures

Abstract

A spectrophotometric study has been made of the formation of complexes between the alkali chlorides and benzo-18-crown-6 incorporated in poly(vinyl alcohol) in aqueous dioxane and tetrahydrofuran. The variations of the apparent complex formation constants with solvent composition are interpreted in terms of the activity of water in the solvent mixtures. The intrinsic complex formation constant for each cation has been determined as a single value irrespective of the type or composition of the solvent mixtures. The complex formation liberates ca. 3 mol of water from around the cations.