An investigation of factors influencing the resolution of chiral alkyl aromatic amines on a dinitrobenzoyl-(S)-leucine HPLC column

Normal phase HPLC methodology was utilised to obtain separation of (±)-1-(4-bromophenyl)ethylamine and (±)-1-(1-Naphthyl)ethylamine on a 3,5-dinitrobenzoyl-(S)-Leucine Pirkle type chiral stationary phase (CSP). A proposed retention mechanism (based on a three point interaction model) is outlined where the key interaction is steric attraction/repulsion between aryl groups on the solutes and the (S) Leucine group on the CSP.