Two New Cubane-Type Tetranuclear Compounds of Copper(II), Nickel(II) Derived from Reduced Schiff Base Ligand: Syntheses, Structures and Magnetic Properties

Two tetranuclear complexes, [M(H3L)](4)center dot X (1, M = Cu, X = 4,4'-dpdo; 2, M = Ni, X = DMF, H5L = 2-[(3,5-dibromo-2-hydroxybenzyl) amino]-2-(hydroxymethyl)propane-1,3-diol, 4,4'-dpdo is 4,4'-bipyridine-N,N'-dioxide, DMF = N,N'-dimethyl formamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Compound 1 features a centrosymmetric tetranuclear copper cluster which further constructed a 1D chain through a tetra-acceptor hydrogen bonds of 4,4'-dpdo molecule. Compound 2 having a P2(1) /n space group also exhibits a tetranuclear nickel cluster with a cubane topology in which the central Ni(II) ion and oxygen atoms from H3L2- occupy the alternate vertices of the cube. Magnetic properties of 1 and 2 in the 2-300 K have also been discussed. The tetranuclear cubanes cores display dominant ferromagnetic interactions.