Enantioselective lactate binding by chiral tripodal anion hosts derived from amino acids

Chiral, tripodal anion hosts derived from either S-phenylalanine or S-leucine bind d-lactate enantioselectively. The nature of the host-guest interaction has been probed by solution NMR methods and by DFT calculations. The calculations suggest that the d-lactate may form an additional hydrogen bond in the host-guest complex while the l-lactate complex contains an intramolecular hydrogen bond. Anion binding is in competition with host dimerisation, as demonstrated by DOSY and ¹H NMR spectroscopy, and DFT calculations. © 2009 The Royal Society of Chemistry.