Dicopper Complexes with a Dissymmetric Dicompartmental Schiff Base−Oxime Ligand: Synthesis, Structure, and Magnetic Interactions

Abstract

A dicopper(II) complex with an unsymmetrical dicompartmental ligand containing bridging phenolic oxygen atoms was synthesized by stepwise condensation, in the presence of copper(II) ions, of 2,6-diformyl-4-methylphenol and diaminopropane, followed by hydroxylamine. The complex was isolated and characterized as Cl-, [Cu2Cl4]2-, and ClO4- derivatives. A byproduct of the reaction, a copper(II) complex with a substituted salycilaldoxime, was also structurally characterized. The structure of the binuclear cation of major interest is nearly planar, with the copper(II) ions slightly displaced to opposite sides of the plane of the donor atoms (<0.20 A). [Cu2Cl4]2- is an unusual anion, having been characterized previously in only five other compounds. It is flat, with both copper(I) ions in trigonal planar environments and two chlorides bridging the two copper(I) centers. X-ray structure determinations of the [Cu2Cl4]2- and ClO4- derivatives of the dicopper complex reveal a strong tendency for the formation of coo...