Synthesis and crystal structure of two Co(III) α-dioximates with the formula [Co(DH)2(PPh3)(H2O)]2[EF6]·nH2O

Abstract

The [Co(DH)2(PPh3)(H2O)]2[TiF6]·2.5H2O (1) and Co(DH)2(PPh3)(H2O)]2[ZrF6]·3.75H2O (2) complexes have been obtained from the CoEF6·6H2O - 2DH2 - PPh3 system, where DH2 is the dimethylglyoxime, E is Ti or Zr, and PPh3 is triphenylphosphine. The structure and composition of these complexes have been elucidated by means of modern physical methods: element analysis, spectroscopy in UV-Vis, IR, NMR 1H, 19 F, X-ray investigation. The Co(III) cation’s coordination polyhedron consists of four nitrogen atoms of dimethylglyoxime monoanions, the phosphor atom of triphenylphosphine and the oxygen atom of the water molecule. In the equatorial plane of the complex cation octahedron, two DH- monoanions are linked through intramolecular O–H…O hydrogen bonds. π-π interactions between the phenylic ring of PPh3 and metalocycle have been revealed in the complex cations. In the crystal, the components of compounds 1 and 2 form a complicated system of hydrogen bonds.