Synthesis, structural and solvent influence studies on solvatochromic mixed-ligand copper(II) complexes with the rigid nitrogen ligand: bis[N-(2,4,6-trimethylphenyl)imino]acenaphthene

Three mixed-ligand copper (II) complexes containing the rigid bidentate nitrogen ligand bis[N-(2,4,6-trimethylphenyl)imino]acenaphthene (abbr. 2,4,6-Me3C6H2-BIAN) and β-diketonate (dike) ligands are reported and characterized. These complexes namely, [Cu(dike)(2,4,6-Me3C6H2-BIAN)]ClO4 {where dike=acac (acetylacetonate), bzac (benzoylacetonate) or (dibm) dibenzoylmethanate}have been synthesized and characterized by elemental analysis, spectroscopic, magnetic and molar conductance measurements. In addition to their high solubility in various organic solvents, these three complexes show a color change on going from one solvent to another, that is, strong solvatochromism of their solutions. The observed solvatochromism is mainly due to the solute-solvent interaction between the chelate cation and the solvent molecules. Reported also are the X-ray crystal structures of the free 2,4,6-Me3C6H2-BIAN ligand and the [Cu(acac)(2,4,6-Me3C6H2-BIAN)]ClO4 complex. © 2004 Elsevier B.V. All rights reserved.