CU(II) AND NI(II) COMPLEXES OF N,N'-BIS(2-AMINOETHYL)-OXAMIDE AND N,N'-BIS(3-AMINOPROPYL) OXAMIDE - A POTENTIOMETRIC AND SPECTROPHOTOMETRICSTUDY

Extensive potentiometric and spectrophotometric (visible region) data resulted in the unravelling of the complete details of complex formati on of N,N'-bis(2-aminoethyl) oxamide (L(1)) and N,N'-bis(3-aminopropyl ) oxamide (L(2)). This study reveals both similarities and differences in complex formation for these ligands. Earlier reports gave evidence for the formation of a Cu(3)L(2)H(-4) complex of L(2). We show that L (1) forms a Cu(2)L(2)H(2), complex. This difference in behaviour is du e to a decrease in stability of the CuLH(-2) complex of L(2) compared to that of L(1). The complexation of Ni2+ by L(1) is also discussed.