Crystal structure of [Cu(H2O)2(4,4'-bpy)](ClO4)2 (4,4'-bpy).

coordination chemistry is currently of great interest in research. The use of transition-metal centers and coordination chemistry for directing the formation of complex structures has evolved into one of the most widely used strategies for organizing molecular building blocks into supramolecular arrays.1–3 Assembling extended supramolecular architectures by selecting the chemical structure of organic ligands and the coordination geometry of metal ions may produce novel network solids with potential utility as novel materials. Bidentate ligands, such as 4,4′-bipyridine, have been widely employed for the synthesis of coordination polymers; thus, a large number of 4,4-bipyridine networks have been reported, including 1D chains, 2D grids or 3D frameworks.4–6 The title compound was prepared from the reaction of an aqueous solution of Cu(ClO4)2·6H2O (1.0 mmol) and 4,4′bipyridine (2.0 mmol) in EtOH. Single-crystals suitable for an X-ray diffraction study were obtained by slow diffusion of an ethanol solution of 4,4-bipyridine into an aqueous solution of Cu(ClO4)2·6H2O. Data collection was performed on an Enraf-Nonius CAD4 diffractometer using monochromatized Mo Kα radiation (λ = 1179 ANALYTICAL SCIENCES OCTOBER 2002, VOL. 18 2002 © The Japan Society for Analytical Chemistry