Crown thioether chemistry.

The synthetic, structural, and coordination chemistry of crown thioethers with both transition and p-block metal ions is reviewed comprehensively through December 1988. Emphasis falls upon the electronic structures and redox properties induced in metal ions by coordination to crown thioethers. Examples include stabilization of mononuclear Rh(II), Pt(III), and low-spin octahedral Co(II). A subsidiary theme concerns the influence of ligand conformation in determining both the binding efficacy and the qualitative coordination chemistry associated with a given crown thioether. The review concludes with a view toward potential future applications of crown thioethers in catalysis, in sequestration or biological delivery of heavy metal ions, and in fundamental studies directed toward rational design of ligands. [ABSTRACT FROM AUTHOR]