Metal–α,ω-Dicarboxylate Complexes. I. Aqua(2,2'-bipyridyl-N,N')(malonato-O,O')copper(II) Monohydrate

The title compound, [Cu(C3H2O4)(C10H8N2)(H2O)].H2O, exists as discrete monomers. The CuII ion is square pyramidal, with two N atoms of the bipyridyl ligand and two O atoms, one from each of the carboxylates of the folded dibasic acid, providing the base and a water molecule forming a long apical bond [Cu—O5 2.523 (3) A]. The `scorpion-like' complex possesses a plane of symmetry bisecting the molecule lengthwise, the non-planarity arising from severe puckering of the six-membered chelate ring of the acid. Hydrogen-bonding interactions between the water molecules and the carboxylate O atoms stabilize the crystal structure.