Five mono-nuclear Cu(II) and Ni(II) complexes and one dinuclear Zn(II) complex were synthesized from the Schiff bases N,N'-bis(3-ethoxy-2-hydroxybenzylidene)-1,2-phenylenediamine (H 2 L OEt -phda) and 2-ethoxy-6-({2- [(3-ethoxy-The complexes were structurally characterized with elemental microanalyses, IR, UV-Vis and ESI-MS spectroscopic techniques as well as single crystal X-ray crystallography. The metal centers display distorted square planar geometries in 2-4 and 5 and distorted square pyramidal (SP) in 1, whereas in 6 an intermediate geometry between SP and TBP was observed around the first Zn 2+ ion and a tetrahedral around the second ion, with one acetate is acting as a bridging ligand. In all cases, metal ions were incorporated into the N 2 -O 2 binding site with no involvement of the alkoxy groups in the coordination. The L OEt -ambza-complexes 3-6 revealed significant dihedral angles between the phenol rings and the plane containing the central benzene ring, and large O 2 -O 2 bond distances (5.1-5.9Ǻ). Results are discussed in relation to other related Schiff base complexes.

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