A new chiral lanthanide NMR probe for the determination of the enantiomeric purity of α-hydroxy acids and the absolute configuration of α-amino acids in water
Abstract
A water-soluble, enantiopure lanthanide complex, SSS-[Ln·L3], has been assessed as an effective chiral derivatising agent for the determination of the enantiomeric purity of α-hydroxy acids in aqueous solution. The complex displays superior chemical shift non-equivalence (ΔΔδ
∼2–11 ppm) for the diastereomeric resonances of interest compared to lanthanide shift reagents reported in the literature (ΔΔδ <0.1 ppm, typically).