Preparation, Characterization and Crystal Structure of [Cu2(O2CH)4(nicotinamide)2]

The novel copper(II) coordination compound, [Cu2(O2CH)4(nia)2] (nia = nicotinamide), was isolated from the reaction mixture containing Cu2(OH)2CO3, nicotinamide, methanoic acid and ethanol. The new complex was characterized by X-ray single crystal diffraction and other standard physico-chemical methods. The structure contains binuclear centrosymmetric molecules in which two central atoms are bridged by four methanoate bridges forming a paddle-wheel structure type. The fifth coordination site completing the distorted square pyramid around copper is occupied by aromatic nitrogen of nicotinamide. The molecules pack together via hydrogen bonds resulting in a formation of extended supramolecular sheets. The results of other physical measurements are also in a complete agreement with the obtained structure.