Synthesis, spectroscopic, and structural characterization of mixed thioether–benzimidazole copper complexes
作者:Ivan Castillo、Brenda N. Sánchez-Eguía、Paulina R. Martínez-Alanis、Víctor M. Ugalde-Saldívar、Marcos Flores-Alamo
DOI:10.1016/j.poly.2014.10.022
日期:2015.1
Mixed N,S tripodal ligands bis(2,4-dimethylphenylthioethyl)(2-methylbenzimidazolyl)amine L-1, bis(2,4-dimethylphenylthioethyl)(1-methyl-2-methylbenzimidazolyl)amine L-2, and bis(1-methyl-2-methylbenzirnidazolyl)(2-methylthioethyl)amine L-3 were employed to prepare the corresponding copper complexes. L-1 and L-2 associate weakly with Cu2+, while the reaction of CuI with L-1 affords [(LCuI)-Cu-1]. This was characterized in the solid state by the chelating tridentate coordination mode of L-1, with a free thioether, and a terminal iodide, in contrast with the commonly observed Cu-I-Cu bridges. For L-3, Cu+ and Cu2+ complexes are accessible as [L3Cu]PF6, and the crystallographically characterized [(LCuCl)-Cu-3]Cl. The latter has a square pyramidal coordination around the Cu2+ ion, with the thioether as an axial ligand that remains coordinated in solution, as evidenced by UV-Vis spectroscopy. (C) 2014 Elsevier Ltd. All rights reserved.