Crystal Structure Of Catena-Poly[[Di­Aqua­Bis­(4-Formyl­Benzoato-Κo 1)Cobalt(Ii)]-Μ-Pyrazine-Κ2 N:N′]

Abstract

The CoII atom in this one-dimensional coordination polymer, with aqua, 4-formyl­benzoate and bridging pyrazine ligands, is located on a twofold rotation axis and has a slightly distorted octa­hedral coordination sphere. Strong intra­molecular O—H⋯O hydrogen bonds link the water mol­ecules to the carboxyl­ate O atoms., In the title polymeric compound, [Co(C8H5O3)2(C4H4N2)(H2O)2]n, the CoII atom is located on a twofold rotation axis and has a slightly distorted octa­hedral coordination sphere. In the equatorial plane, it is coordinated by two carboxyl­ate O atoms of two symmetry-related monodentate formyl­benzoate anions and by two N atoms of two bridging pyrazine ligands. The latter are bis­ected by the twofold rotation axis. The axial positions are occupied by two O atoms of the coordinating water mol­ecules. In the formyl­benzoate anion, the carboxyl­ate group is twisted away from the attached benzene ring by 7.50 (8)°, while the benzene and pyrazine rings are oriented at a dihedral angle of 64.90 (4)°. The pyrazine ligands bridge the CoII cations, forming linear chains running along the b-axis direction. Strong intra­molecular O—H⋯O hydrogen bonds link the water mol­ecules to the carboxyl­ate O atoms. In the crystal, weak O—Hwater⋯Owater hydrogen bonds link adjacent chains into layers parallel to the bc plane. The layers are linked via C—Hpyrazine⋯Oform­yl hydrogen bonds, forming a three-dimensional network. There are also weak C—H⋯π inter­actions present.