Design of chiral monochloro-s-triazine reagents for the liquid chromatographic separation of amino acid enantiomers

A series of chiral derivatizing reagents (CDRs) was synthesized by nucleophilic replacement of one chlorine atom in cyanuric chloride (2,4,6-trichloro-1,3,5-triazine; s-triazine) by alkoxy (methoxy, butoxy, 1,1,1-trifluoroethoxy) or aryloxy groups (phenoxy, nitrophenoxy, phenylphenoxy, 4-methylcoumaryloxy), and displacement of a second chlorine by l-alanine amide, l-phenylalanine amide, l-proline tert.-butyl ester, or Boc-l-lysine tert.-butyl ester. Further, CDRs were investigated in which two chlorine atoms in cyanuric chloride were substituted consecutively by l-valine amide and l-phenylalanine amide. The resulting CDRs having a remaining reactive chlorine were tested for their capability of derivatizing dl-amino acids followed by liquid chromatographic separation of the resulting diastereomers.