Cyclic Polylactones and their Cyclic Polyorthoester Valence Tautomers: Potential Ionophores

Abstract

The geometries and energies of the cyclic hexamer ( 9) of glycolic acid, and its polycyclic orthoester valence tautomer ( 10) have been studied by ab initio molecular orbital calculations at the HF/6-31G ∗ and MP2//HF/6-31G ∗ levels of theory. Both molecules are preorganised to bind metal ions in both endohedral and exohedral modes. The binding of 9 and 10 with Li +, Na +, K +, Be 2+, Mg 2+, B 3+ and Al 3+ have been examined, and the energies and geometries of the resulting complexes are discussed.