Supramolecular assembly of nanometer-sized heterobimetallic 3d-4f complexes formed with benzimidazole based N,O-donor ligands

Five heterobimetallic Cu-Ln complexes of general formula [CuLn(HL)(2)(NO3)(3)(MeCN)(2)] center dot 2Et O-2 (Ln = Eu 1, Tb 2, Er 3, Yb 4 and Nd 5) were prepared with a new multidentate benzimidazole ligand based on 4-bromo-2-[2-(5-bromo-2-hydroxy-3-methoxy-phenyl)benzoimidazol-1-ylmethyl]-6-methoxy-phenol (H2L1) or its bis-methoxy substituted analog (H2L3). In the solid state the structures of 1-4 exhibit supramolecular 3D-networks which are formed by the linking of C-H center dot center dot center dot O and C-H center dot center dot center dot pi interactions. Compound 5 does not exhibit an extended supramolecular network. (c) 2005 Elsevier Ltd. All rights reserved.