COPPER(II) AND COPPER(I) COMPLEXES OF TWEEZER LIGANDS - INFLUENCE OF SUBSTITUENTS ON THE TRANSPORT OF COPPER(II) IONS ACROSS LIQUID MEMBRANES

''Tweezer'' ligands obtained by the condensation of 2,9-diformyl-1,10-phenanthroline and o-substituted aromatic primary amines were used for the syntheses of copper(II) and copper(I) complexes. By varying the nature of the ortho substituent on the aromatic primary amine, several ligands were obtained which form 1 : 1 complexes. When the substituent was any one of the F, Cl, Br or CH3 groups, monomeric complexes were obtained. With OCH3 and SCH3 groups as substituents the formation of loosely held dimers was proposed from spectral, ESR and magnetic results. Ligands of the latter type were shown to be effective carriers for the transport of CU2+ ions across organic liquid membranes.