Trinuclear tris-Co(II) and trans-cobaloxime type Co(III) complexes prepared from Co(II) triflate precursor: Synthesis, structure and properties

Three new coordination compounds, [Co3(DH)6] · 24H2O (I), [Co(DH)2Tu2]CF3SO3 (II) and [Co(DH)2Py2]CF3SO3 (III) (where DH− = monoanion of dimethylglyoxime, Py = pyridine, Tu = thiourea), were synthesized starting from Co(CF3SO3)2 · 6H2O as a substrate. The complexes were characterized by X-ray crystallography, spectroscopic methods (IR, UV–Vis, 1H and 13C NMR, MS) and magnetochemistry. Compound I is a neutral, C3i symmetrical, trinuclear Co(II) complex with two tris-{Co2+(μ-DH)3} units connected to the central Co(II) ion via bridging oxygen atoms, saturating the Co(II) octahedral coordination. In the case of II and III, the complex cations have the usual trans-octahedral configuration with two DH-chelating units in the equatorial plane of the Co(III) ion and the apical coordination sites occupied by two neutral monodentate ligands (Py or Tu).

Graphical abstractThree new coordination compounds, one trinuclear tris Co(II):[Co3(DH)6] · 24H2O (I), and two mononuclear trans: [Co(DH)2Tu2]CF3SO3 (II) and [Co(DH)2Py2]CF3SO3 (III) (where DH− = monoanion of dimethylglyoxime, Py = pyridine, Tu = thiourea), were synthesized starting from Co(CF3SO3)2 · 6H2O. The complexes were characterized by X-ray crystallography, spectroscopic methods (IR, UV–Vis, 1H and 13C NMR, MS) and magnetochemistry.Figure optionsDownload full-size imageDownload as PowerPoint slide