Transition metal complexes with Girard reagent-based ligands, Part I: Synthesis and crystal structure of the first cobalt(III) complexes with Schiff base derivative of Girard reagent

Abstract

A new ligand, pyridoxilidene Girard-T hydrazone, [H3L]Cl 2 • 2H2O, and its octahedral cobalt(III) complexes [Co(HL)(NO2)3] • H2O (1) and [Co(HL) 2](PF6)3 (2) were synthesized and characterized by different physical measurements. The crystal structure of (1) has been determined by single crystal X-ray analysis. The crystal packing of the complex molecules is influenced by the presence of weak C-H...π and C-H...O interactions. A new ligand, pyridoxilidene Girard-T hydrazone, [H 3L]Cl2 • 2H2O, and its octahedral cobalt(III) complexes [Co(HL)(NO2)3] • H2O (1) and [Co(HL)2](PF6)3 (2) were synthesized. The X-ray analysis of (1) showed that the complex has a mer-octahedral configuration formed by coordination of the tridentate ONO neutral Schiff-base molecule and three monodentate N-bonded NO2 groups. Hydrogen bonds and intermolecular interactions for this complex are discussed. Complex (2) also has a mer-octahedral configuration. The ligand and complexes were characterized by elemental analysis, conductometric and magnetochemical measurements, IR and UV-Visible, 1H and 13C NMR spectra. © 2004 Published by Elsevier B.V.