Crystal Structure and Magnetic Properties of a Binuclear Copper(II) Complex Bridged by an Alkoxo-oxygen Atom and an Acetate Ion

[Cu4(L)2(O2CMe)2] H2O (L = 1,3-bis(5-bromo-2-hydroxybenzylidene)propan-2-ol) was synthesized and its crystal structure determined. (C38H34N4O10Br4Cu4)·H2O, monoclinic, space group P21/c, a = 21.072(5), b = 9.673(2), c = 21.934(4) Å, β = 109.73(2)°, V = 4208(2) Å3, Z = 4. The crystal structure consists of two independent binuclear copper(II) complexes and the non-coordinating water molecule in the asymetric unit. The Cu(II) ions are in a square-planar geometry and coordinated by donor atoms of the ligand (NO3). The average Cu···Cu distance and average Cu-O-Cu angle are 3.491(2) Å and 132.0(1)°, respectively. Temperature-dependent magnetic susceptibility measurements of the complex show an intramolecular anti ferromagnetic coupling in the dimeric Cu(II) core. The fitting parameters are -2J = 174.4 cm-1, g = 1.98.