Determination of amino acid enantiopurity and absolute configuration: synergism between configurationally labile metal-based receptors and dynamic covalent interactions.

Reliable determination of the enantiomeric excess of free amino acids can be obtained by measuring the induced circular dichroism of a multicomponent assembly formed by a modified tris(2-pyridylmethyl)amine ligand, a zinc salt, and the amino acid of interest. The systems furnish reliable information for all natural amino acids.