Structural and Magnetic Properties of Two Copper(II) Complexes Based on Dinuclear Copper(II) Metallacyclophane

Two new oxamato‐bridged copper(II) complexes of formula Na10[{Cu2(mpba)2}2(μ1,1‐N3)2]·18H2O (1) and [{Cu2(mpba)2}Cu2(H2O)8]·6H2O (2) [mpba = 1,3‐phenylenebis(oxamato‐N,N′)] have been synthesized and characterized. X‐ray crystallographic studies of complex 1 reveal a metallamacrocycle structure in which two dinuclear copper(II) metallacyclophane anions are linked by two single symmetric azido ligands in an end‐on mode at axial–axial positions. These metallamacrocycle units are self‐assembled through sodium cations and water molecules, affording an intricate 3D network. Complex 2 consists of 2D brick‐wall‐like layers assembled from dinuclear metallacyclophane [Cu2(mpba)2]4– anions and copper(II) cations. Magnetic susceptibility measurements of complex 1 in the temperature range 2–300 K show dominating ferromagnetic coupling mediated by the m‐phenylenediamide bridge and weak antiferromagnetic interaction transmitted by the azido ligand.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) Two new (oxamato)copper(II) complexes have been synthesized in the presence of the azido ligand. The first complex has a metallamacrocycle structure in which two dinuclear copper(II) metallacyclophane anions are linked by two azido ligands, and the second is a 2D brick‐wall‐like layer structure. The magnetic properties of the metallamacrocycle complex are analyzed in connection with its structure.