Cyclodextrin Derivatives as Chiral Selectors—Investigation of the Interaction with (R,S)‐Methyl‐2‐chloropropionate by Enantioselective Gas Chromatography, NMR Spectroscopy, and Molecular Dynamics Simulation

The greater stability of the complex of methyl (S)-2-chloropropionate ((S)-1) and the hydrophobic cyclodextrin derivative 2, is deduced from its characterization by gas chromatography and NMR spectroscopy as well as from molecular dynamics simulations of the (R,S)-1/2, (R)-1/2, and (S)-1/2 systems: on complexation the 1H NMR signals of the (S) enantiomer undergo a downfield shift of up to Δδ = 0.5 relative to those of the (R) enantiomer. Thus, cyclodextrins can be used not only for enantiomeric separations, but also as chiral shift reagents. R2 = R6 = n-pentyl, R3 = acetyl.