The determination of the stability constants of four silver(I) crown thioether complexes

In order to develop practical applications for crown thioether compounds and their transition metal complexes, the stability of the complexes must first be determined. The stability constants for the complexes formed between Ag+ and four crown thioether compounds; [9]aneS₃, [12]aneS₄, [14]aneS₄, and [18]aneS₆ were measured in this project. The ligands differ in the number of donor atoms and macrocyclic cavity size. The effects of both the solvent and ionic strength buffer salt on the stability of the [9]aneS₃ complex were examined. The results indicate that [18]aneS₆ forms the strongest complex with the silver(I) ion. The silver(I) ion forms a 1:1 complex with [9]aneS ₃ that is not affected by the compound used for the ionic strength buffer. An undefined ligand-metal interaction with [14]aneS₄ was observed; [12]aneS₄ formed a 1:1 complex with silver(I).