SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF THE Co(III) COMPLEX WITH 2'-[1-(2-PYRIDINYL)-ETHYLIDENE]-OXAMOHYDRAZIDE (Hapsox): THE CRYSTAL STRUCTURE OF BIS-{2'-[l-(2-PYRIDINYL)-ETHYLIDENE]-OXAMOHYDRAZIDO} COBALT(III) PERCHLORATE, [Co(apsox)_2]ClO_4

摘要

The synthesis of a novel ligand 2'-[1-(2-pyridinyl)-ethylidene]-oxamohydrazide (Hapsox), from a series of 2-acetylpyridine acylhydrazones, and its complex with Co(III), which is the first in this series of complexes are described. Both the ligand and the complex were characterized by elemental analysis, IR, ~1H-NMR, and ~(13)C-NMR spectra, and the structure of the complex [Co(apsox)_2]ClO_4 was determined by X-ray structural analysis. It was established that [Co(apsox)_2]ClO_4 has an octahedral geometry with two tridentate apsox ligands in monoanionic form. Structural characteristics, lengths of the bonds, and angles between the bonds were typical for Co(III) complexes of distorted octahedral geometry. Both direct and template synthesis afforded the same geometrical isomer of the complex with two apsox ligands meridionally bound to the central metal ion, even in the case when equimolar quantities of Co(ClO_4)_2 and Hapsox were applied.