Solid State Characterization of One‐ and Two‐Electron Oxidized CuII‐salen Complexes with para‐Substituents: Geometric Structure‐Magnetic Property Relationship

Abstract

AbstractOne‐ and two‐electron oxidized CuII complexes of Schiff base ligands with para‐substituted phenolate moieties were synthesized and characterized. The crystal structure of the one‐electron oxidized methylthio‐substituted complex [Cu(MeS‐salen)]SbCl6 revealed the intermolecular π‐π stacking interaction of the two phenolate moieties with those of the neighboring complex cations to form the one‐dimensional chain. Such a π‐π stacking interaction could not be detected in the two‐electron oxidized complex [Cu(MeS‐salen)](SbCl6)2 and the oxidized methoxy‐substituted complexes [Cu(MeO‐salen)](SbF6)n (n=1, 2). Magnetic study of [Cu(MeO‐salen)]SbF6 showed a weak antiferromagnetic interaction between the CuII ion and phenoxyl radical unpaired electron spins, while [Cu(MeS‐salen)]SbCl6 showed a ferromagnetism. Both of the two‐electron oxidized complexes exhibited a relatively strong magnetic interaction between the two radical electrons, while the signs of the electron spins are different.