Structural Chemistry, 19(5), p. 749-755 (2008); doi:10.1007/s11224-008-9358-z
Copper(II) and cobalt(II) complexes of salicylaldimine obtained by the condensation of N,N-diethyl- 2-methyl-1,4-phenylenediamine with 3,5-di-tert-butyl- 2-hydroxybenzaldehyde have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, cyclic voltammetry, and FT-IR and UV–Vis spectroscopy. The molecular structure of the title copper(II) complex was determined by the single crystal X-ray diffraction technique. The Cu(II) center is coordinated by four atoms of the donor set in a compressed tetrahedral trans- [N2O2] environment, which can be essentially ascribed to the presence of bulky fragments of the ligand. The computed bond valences of the copper verify +2 oxidation state and indicate that the copper bonds, in particular Cu–N bonds, are elongated due to steric effects from bulky substituents in the ligands, N-(4-diethylamino-2-methylphenyl). Intermolecular C–H···p interactions leading to centrosymmetric synthons serve to stabilize periodic organization of the molecules.