Structural and magnetic characterization of a linear trinuclear copper complex formed through ligand sharing

Reaction of bis(2-hydroxybenzyl)-1,3-diamino-2-propanol (H(2)bhbdp) with copper perchlorate in methanol leads to the assembly of a trinuclear complex with the general formula [Cu-3(bhbdp)(2)(CH3OH)(2)(ClO4)(2)] (1). The complex was characterized by X-ray crystallography, Ligand Field, IR and ESR spectroscopy, and magnetic susceptibility. The structure of the complex contains a linear trinuclear array of copper ions [the Cu(1)-Cu(2)-Cu(1a) angle is 180degrees by symmetry], in octahedral, square planar and octahedral environments, respectively. The external Cu1 and Cu1a centers are coordinated by two amine nitrogens, two phenolate oxygen donors, one methoxide oxygen and one oxygen from a perchlorate, while the central Cu2 is coordinated by four phenolate oxygens through ligand sharing. A strong antiferromagnetic interaction between the adjacent Cu-II ions dominates the magnetic properties of 1 leading to an S = 1/2 ground state which is fully populated below 150 K. (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.