Synthesis, Crystal Structure, Spectral and Thermal Characterization of Bis(o-Vanillinato) and Bis[(R)-(O-Vanillinato]Copper(II)

Abstract

The novel complexes bis(o-vanillinato)-triethylenglycoldiiminecopper(II) (1) and bis[(R)-(-)-hydroxymethylpropylimine o-vanillinato]copper(II) (2) have been synthesized and characterized by elemental analysis, magnetic susceptibility, spectral methods (UV-Vis and FT-IR), simultaneous TG, DTA techniques and X-ray diffraction. The crystal structure of (1) determined that the Cu atom is coordinated by two imine N atoms and two phenol O atoms from the Schiff base ligand in a slightly distorted square-planar coordination. The o-vanillinato ligands moieties of the molecule are in a trans configuration and the dihedral angle between the aromatic ring planes is 43.97(14)°. Compound (2) crystallizes in the triclinic space group P over(1, ̄) with unit-cell parameters a = 8.054(7), b = 8.684(7), c = 10.258(8) Å, α = 79.452(6)°, β = 70.454(6)°, γ = 65.427(6)° and Z = 1. The crystal structure of (2) has indicated that the complex is slightly distorted square planar and is chelated by the two imine N atoms and two phenol O atoms from the Schiff base ligand. The o-vanillinato ligands moieties of (2) are in a trans configuration and the torsion angle between the aromatic ring planes is 60.5(3)°. The crystal packing involves both hydrogen-bonding and C-H⋯π interactions. Thermal analyses showed that the title compounds decompose in two stages over the temperature range 20-1000 °C in a static air atmosphere. © 2009 Elsevier Ltd. All rights reserved.