14337-09-8Relevant articles and documents
Models for Copper-Dioxygen Complexes: the Chemistry of Copper(II) with Some Planar Tridentate Nitrogen Ligands
Piguet, Claude,Bocquet, Bernard,Mueller, Edgar,Williams, Alan F.
, p. 323 - 337 (2007/10/02)
The solution chemistry of Cu(II) with a series of five planar tridentate nitrogen ligands, 2,6-bis(benzimidazol-2-yl)pyridine (bzimpy, 1), 2,6-bis(1-methylbenzimidazol-2-yl)pyridine (mbzimpy, 2), 2,6-bis(benzothiazol-2-yl)pyridine (bzthpy, 3), 2,6-bis(benzoxazol-2-yl)pyridine (bzoxpy, 4), and 2,2',6',2"-terpyridyl (terpy, 5) is reported.Electronic and EPR spectra are consistent with the complexes 2+ having essentially tetragonal structure in solution, with the fourth coordination site in the plane of the ligand occupied by solvent. bzthpy and bzoxpy show smaller ligand-field splittings than bzimpy, mbzimpy, and terpy, and are easily decomplexed from the copper.Substitution of the coordinated solvent molecule in the plane of the ligand is observed with Cl- and OH- (provided that the ligand has no acidic protons) for all ligands except terpy.The reaction between 2+ and imidazole has been studied by potentiometric titration in MeCN/H2O 1:1 and shows strong binding of the imidazole in the plane (log K = 4.5 at 25 deg C), and also the formation of an imidazolate-bridged dinuclear species.