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Tri-nuclear cobalt and nickel complexes ([(CoL)2(OAc)2Co] · THF (I) and [(NiL)2(OAc)2(THF)2Ni] · THF (II)) have been synthesized by reaction of a new Salen-type bisoxime chelating ligand of 2,2'-[ethylenedioxybis(nitrilomethylidyne)]dinaphthol(H2L) with cobalt(II) acetate tetrahydrate or nickel(II) acetate tetrahydrate, respectively. Complexes I and II were characterized by elemental analyses, IR, TG-DTA and 1H-NMR etc. The X-ray crystal structures of I and II reveal that two acetate ions coordinate to three cobalt or nickel ions through M-O-C-O-M (M = Co or Ni) bridges and four μ-naphthoxo oxygen atoms from two [ML] units also coordinate to cobalt(II) or nickel(II). Complex I has two distorted square-pyramidal coordination spheres and an octahedral geometry around Co1. In complex II all three nickel ions are six-coordinate. [ABSTRACT FROM AUTHOR]

A novel trinuclear nickel (II) cluster {[NiL(EtOH)]2(OAc)2Ni} · 2EtOH has been synthsized and characterized by elemental analyses, TG-DTA, IR and 1H-NMR etc. The X-ray crystallography of the cluster indicates that the ligand moieties of the cluster provide the N2O2 donors set to Ni2, while one oxygen atom of the μ-acetato and one oxygen atom of the ethanol molecule coordinate to Ni2, consequently forming a slightly distorted octahedral geometry. The double μ-acetato bridges adopt the more familiar μ O-C-O form which connect the Ni2-Ni1 and Ni1-Ni2#, respectively, so quadruple µ-phenoxo oxygens from 2 ligand moieties and double oxygen atoms from µ-acetato constitute another octahedral geometry. It is worthy noting that the distance from the Ni1 to Ni2 (3.089Å) is significantly longer than other coordination bond, shows a weaker interaction. In addition, the HOMO and LUMO levels of the cluster were deduced. [ABSTRACT FROM AUTHOR]