In the title compound, [Co(SO4)(C12H8N2)2]·C2H6O2, a twofold rotation axis passes through the Co and S atoms, and through the mid‐point of the solvent C—C bond. The coordination environment of the CoII centre is a distorted CoN4O2 octa­hedron, with four N atoms from two chelating 1,10‐phenanthroline ligands and two O atoms from a bidentate sulfate ligand. The two chelating N2C2 groups are oriented at 70.16 (6)° to each other. Inter­molecular O—H⋯O hydrogen bonds help to stabilize the structure.

Key indicatorsSingle-crystal X-ray study T = 293 K Mean (C-C) = 0.005 Å R factor = 0.031 wR factor = 0.077 Data-to-parameter ratio = 17.9For details of how these key indicators were automatically derived from the article, see

In the title compound, {[Co(SO4)(C10H8N2)(H2O)3].C2H6O2}n, each CoII center is octahedrally coordinated by two N atoms from two bridging 4,4'-bipyridine (bipy) ligands and four O atoms, one from a monodentate sulfate ligand and three from aqua ligands. The bipy ligands occupy special positions of site symmetry -1 and bridge adjacent cobalt(II) centers to form one-dimensional linear coordination chains. Adjacent chains are arranged in a cross-like fashion around the mid-point of the bipy ligands, resulting in a three-dimensional supramolecular array.

In the structure of the title compound, [Ni(SO4)(C12H8N2)2]·C3H8O2, the NiII ion (site symmetry 2) is six-coordinated in a distorted octa­hedral manner by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and two O atoms from a bidentate sulfate ligand (2 symmetry). The dihedral angle between the two chelating NCCN groups is 80.9 (1)°. The central C atom of the propane-1,3-diol solvent mol­ecule is likewise located on a twofold rotation axis. In the crystal structure, the [Ni(SO4)(C12H8N2)2] and C3H8O2 entities are connected through inter­molecular O—H⋯O hydrogen bonding.

In the preparation of the title hydrated salt, C14H13N2 +·C10H5O8 −·H2O, a proton has been transfered to the 2,9-dimethyl-1,10-phenanthrolinium cation, forming a 2,4,5-tri­carb­oxy­benzoate anion. In the anion, the mean planes of the protonated carboxyl­ate groups form dihedral angles of 11.0 (5), 4.4 (5) and 80.3 (4)° with the benzene ring to which they are attached. The mean plane of the deprotonated carboxyl­ate group forms a dihedral angle of 10.6 (5)° with the benzene ring. In the crystal, the anions are involved in carb­oxy­lic acid O—H⋯Ocarbox­yl hydrogen bonds, generating a two-dimensional network parallel to (001) containing R 4 4(28) and R 4 4(32) motifs. The 2,9-dimethyl-1,10-phenanthrolinium cations and water mol­ecules reside between the anion layers and are connected to the anions via N—H⋯Owater and Owater—H⋯Ocarbox­yl hydrogen bonds. An intra­molecular O—H⋯O hydrogen bond is also observed in the anion.