Crystal structure of tetraaqua(o-phenanthroline)cobalt(II) sulfate dihydrate, [C12H8N2 )Co(H2O)4]S04 · 2H2O

Abstract

Source of material C0SO4 · 6H2O (1 g) was dissolved in water (5 ml) and was added to íerí-C4H900H (5 ml). With stirring to the solution was added a solution of phenanthroline (5 mmol in 5 ml of acetonitrile). Dichloromethene (5 ml) was carefully injected to the bottom of the above solution. The resulting solution with a clear layer was stood still in air. Five hours later a great amount of light pink crystals suitable for X-ray were deposited at the bottom of the flask. The product was washed with water and methanol, and dried in vacuum under CaCk. Analysis: found: C 32.5%, H 4.5%, Ν 6.18%, C12H20N2O10SC0 requires C 32.5%, Η 4.6%, Ν 6.32%.* Correspondence author (e-mail: hlzhu@wist.edu.cn) DiscussionThe discovery that certain cobalt complexes are potent antiviral agents [ 1 ] prompted us to initiate an investigation of cobalt interactions with proteins and nucleic acids. Since complexes with relatively labile axial ligands exhibit higher activities, Gray and co-workers [2] assumed that axial binding of cobalt to biological targets was somehow involved in the mechanism (or mechanisms) of action. Herein we report the preparation and single and crystal structure of a cobalt(II) complex with two very labile axial H2O ligands. The title complex comprises a discrete phenanthrolinatocobalt(ü) tetrahydrated di-cation, a sulfate anion and two uncoordinated water molecules. In the cation, each cobalt(II) atom is six-coordinated, with two nitrogen atoms from a phenanthroline ligand and four oxygen atoms from four molecules in a slightly distorted octahedral geometry. ) between plane I and the phenanthroline inside the molecule is mostly parallel. Two kinds of one-dimentional chains coming from appreciable phen-phen interactions between the molecules are found. Inside each chain, the phen rings are parallel to each other, and the interplanar distance is 3.45 Â, slightly shorter than that (3.48 Â) in the complex of literature [3]. Between the neighboring chains the phen rings are nearly perpendicular one another with the dihedral angle 77.4(8)°. All oxygen atoms, including those from the sulfate anion, coordinated and uncoordinated water molecules in the title complex, contribute to the formation of hydrogen bonds, and a large number of interlinked inter-and intramolecular hydrogen bonds join the molecules to form a network structure. Criterion for /obs, N(hkl)gi.

Crystal structure of tetra(2-aminopyrimidine)dimethanolato-dicobalt(II) diperchlorate, [Co2(CH3O)2(C4H5N3)4][ClO4]2

“…Recently, there were many cobalt(II, III) complexes being structurally determined by single X-ray analysis [1][2][3][4]. We have been interested in preparing some mono-, di-or trinuclear metal complexes and assaying their biological relevant activities and succeeded in preparing the trinuclear cobalt complexes [5].…”