P. Amudha, P. Akilan, M. Kandaswamy
Mar 12, 1999
Citations
0
Influential Citations
22
Citations
Journal
Polyhedron
Abstract
Abstract New symmetrical 2,6-bis{N-[2-(2-benzimidazolyl)-phenyl]iminomethyl}-4-methylphenol (L1) and unsymmetrical 2-N-[2-(2-benzimidazoyl)phenyl]iminomethyl-6-[(4-methylpiperazin-1-yl)-methyl]-4-methylphenol (L2) binucleating ligands have been synthesized. Complexation of these ligands with Cu(II) perchlorate and appropriate sodium salt offered the binuclear copper(II) complexes, [Cu2L(X)](ClO4)2, (X=Cl, OH and OAc 1–6). Their spectral, electrochemical and magnetic properties have been studied. Two distinct reduction peaks were observed at negative potentials. The electrochemical data shows that the complexes of L2 undergo reduction at less negative potential (E1pc=−0.15 to −0.25 V, E2pc=−0.45 to −0.65 V) when compared to the complexes of L1 (E1pc=−0.45 to −0.58 V, E2pc=−1.07 to −1.103 V). A variable temperature magnetic study on the complexes of the ligand L1 showed strong antiferromagnetic coupling between the copper atoms (−2J=285–295 cm−1), in contrast, the complexes of the ligand L2 showed weak antiferromagnetic interaction (−2J=60–85 cm−1). Electron spin resonance (ESR) spectra (RT) of the complexes of ligand L1 showed no signal and the complexes of ligand L2 showed a broad feature.