Molecular modeling of complexes between two amino acids and copper(II): Correlation with Ligand Exchange Capillary Electrophoresis

The energies of various Cu(II) complexes have been computed at the MM and DFT levels of theory. These complexes are constituted of Cu(II) ion used as a central ion, an enantiomer of an amino acid and l-proline or trans-4-l-Hydroxy-proline (THLP) used as chiral selectors in Ligand Exchange Capillary Electrophoresis (LECE). The energy differences of the diastereomeric complexes containing implicit water molecules computed at the DFT/B3LYP/LANL2DZ level are in good agreement with the observed enantioseparations using LECE.