A new binucleating ligand incorporating four oxime groups and its copper(II), manganese(II) and cobalt(III) complexes

A new binucleating ligand incorporating four oxime groups, butane-2,3-dione O-[4-aminooxy-2,3-bis-(2-hydroxyimino-1-methyl-propylideneaminooxymethyl)- but-2-enyl]-dioxime, (H(4)mto), has been synthesized and its dinuclear coba lt(III), copper(II), and homo- and hetero-tetranuclear copper(II)-manganese (II) complexes have been prepared and characterized by H-1- and C-13-n.m.r. , i.r., magnetic moments and mass spectral studies. Elemental analyses, sto ichiometric and spectroscopic data indicate that the metal ions in the comp lexes are coordinated to the oxime nitrogen atoms (C=N) and the data suppor t the proposed structure for H(4)mto and its complexes. Moreover, dinuclear cobalt(III) and copper(II) complexes of H(4)mto have a 2:1 metal:ligand ra tio.