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 b-diketonate (dike) ligands are reported and characterized. These complexes namely, [Cu(dike)(2,4,6-Me3C6H2-BIAN)]ClO4 {where dike ¼ 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. q 2004 Elsevier B.V. All rights reserved.