Trithiacrown ethers

The equilibrium constants K for thiacrown-ether complexes of dimethylthallium(III) ions obtained in CD3CN are shown in Table III and those of diethyl thallium(III) ions in Table IV. The K values of trithiacrown-ether complexes of dimethylthallium(III) ion are found to be larger than those of diethylthallium(III) ion. The symmetry of ligands also influences these K values. More symmetrical 1,7,13-TTC... 

In contrast to the trithiacrown-ether complexes of dialkylthallium-(III) ions, NMR spectra of monothia- and dithia-crown-ether complexes in CD CN give only signals of complex species [R2TI(L)]C104 and those of free ions and uncomplexed crown-ether were very small if present at all. Therefore, K values of monothia- and dithia-crown-ether complexes of dialkylthallium(III) ions are much larger than those of trithiacrown-... 

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