Thin‐layer gel chromatography of 8‐hydroxyquinoline metal complexes

Abstract

Gel chromatographic behavior of 8-hydroxyquinoline (oxine, abbreviated HOx) complexes of zinc, copper, aluminum, gallium and indium has been investigated on thin layers of Styragel 60A and Merckogel OR-PVA 2000 mostly in chloroform and p-dioxan media. Except for the stable Cu(Ox),, the other oxinates exhibit either hydration or decomposition in gel-solvent-solute systems, which leads to strong retention or tailing on gel layers. An excess of 8-hydroxyquinoline present in solvents allows the oxinates to be stabilized, so that well-defined compact spots come out and migrate. For the Zn(Ox)2 the formation of a selfadduct is strongly suggested on the basis of gel chromatographic behavior. Elution with the solvent containing pyridine also yields evidence of the adduct formation of zinc oxinatenitrogen base.