Poly[trans-diaquabis(μ2-3-pyridylacetato) copper(II)]

The title copperII coordination polymer, trans-[Cu(C7H6NO2) 2(H2O)2] n , was obtained from a solvothermal reaction of 3-pyridylacetic acid hydro-chloride with Cu(ClO4)2·6H2O. The mol-ecule is centrosymmetric, so pairs of equivalent ligands lie trans to each other in a slightly distorted octa-hedral geometry. The CuII center is coordinated by two water mol-ecules [Cu - O = 2.424 (4) Å], two pyridyl N atoms [Cu - N = 2.031 (4) Å], and two carboxyl-ate O atoms [Cu - O1 = 1.968 (4) Å]. All Ocarboxyl-ate - Cu - Ocarboxyl-ate, Owater - Cu - Owater and N - Cu - N bond angles are 180°due to the inversion symmetry of the complexes. Each 3-pyridylacetate anion uses its pyridine N atom and one carboxyl-ate O atom to connect two CuII ions, generating two-dimensional sheets parallel to (212). Each complex exhibits two intra-molecular O - H⋯O hydrogen bonds with angles at hydrogen of 156°. Adjacent two-dimensional layers are connected via inter-molecular O - H⋯O and weak C - H⋯O hydrogen-bonding contacts, resulting in a three-dimensional framework structure with oxygen as a trifurcated acceptor atom. © 2007 International Union of Crystallography. All rights reserved.