Liquid Chromatography of Aza - Arenes

Reversed-phase liquid chromatography (RPLC) makes possible the separation of azaarenes according either to the carbon atom number, with little selectivity toward positional Isomers (long chain packlngs, methanol-water solvent mixtures), or to the position of the nitrogen atom with interferences occurring between compounds of different molecular weight (short chain packings, tetrahydrofuran and acetonitrile- water solvent mixtures). In normal-phase chromatography, the solute retention is malniy governed by the steric hindrance of the nitrogen atom.