Synthesis and evaluation of two novel "mixed" chiral stationary phases deriving from tyrosine: Csps designed for the resolution of either π-acid or π-basic racemates

The synthesis and chromatographic evaluation of two novel chiral stationary phases (CSPs) deriving from (S)‐tyrosine are reported. The chiral graft has been designed in order to bear both π‐acid and π‐basic sites, each one being connected to a distinct asymmetric centre. An intramolecular π‐π interaction may take place within these CSPs, leading to an energetically favoured conformation of the chiral selector (CS). The enantiorecognition ability of these CSPs was investigated for various classes of either π‐acid or π‐basic racemates. It is shown that these CSPs are able to separate simultaneously π‐acid and π‐basic racemates. Finally, chiral recognition mechanisms and mobile phase optimization are discussed.