Chiral Recognition of N ‐Phthaloyl, N ‐Tetrachlorophthaloyl, and N ‐Naphthaloyl α‐Amino Acids and Their Esters on Polysaccharide‐Derived Chiral Stationary Phases

Enantiomeric separations of N ‐phthaloyl ( N ‐PHT), N ‐tetrachlorophthaloyl ( N ‐TCPHT), and N ‐naphthaloyl ( N ‐NPHT) α‐amino acids and their esters were examined on several kinds of polysaccharide‐derived chiral stationary phases (CSPs). Resolution capability of CSPs was greater Chiralcel OF than the others for N ‐PHT and N ‐NPHT α‐amino acids and their esters. In N ‐TCPHT α‐amino acids and their esters, good enantioselectivities showed Chiralcel OG for N ‐TCPHT α‐amino acids, Chiralpak AD for N ‐TCPHT α‐amino acid methyl esters, and Chiralcel OD for N ‐TCPHT α‐amino acid ethyl esters, respectively. From the results of liquid chromatography and computational chemistry , it is concluded that l ‐form is preferred and more retained with electrostatic interaction in case of interaction between N ‐PHT α‐amino acid derivatives and Chiralcel OF, N ‐TCPHT α‐amino acid derivatives and Chiralcel OD, and N ‐NPHT α‐amino acid derivatives and Chiracel OF. On the other hand, d ‐form is preferred and more retained with van der Waals interaction in case of interaction between N ‐TCPHT α‐amino acid ester derivatives and Chiralcel OG and Chiralpak AD. Chirality 24:1037–1046, 2012 . © 2012 Wiley Periodicals, Inc.