ELECTROCHEMICAL STUDIES ON A SERIES OF MANGANESE(III) COMPLEXES CONTAINING SYMMETRICAL PENTADENTATE LIGANDS

The redox properties of a series of manganese(III) complexes incorporating dianionic pentadentate Schiff-base ligands have been examined using cyclic voltammetry. Substituents on the aromatic portion of the ligand and changes on the central donor atom were shown to cause changes in the reduction potentials of the Mn(III) ion. Electron-withdrawing substituents on the aromatic portion of the ligand resulted in a lower reduction potential relative to complexes possessing ligands with electron-donating groups. Changes in the reduction potential were also dependent upon the type of central donor atom and its substituent. Correlation of electrochemical data on these complexes with previously observed reactivity patterns of several of the same complexes with dioxygen and nitric oxide is described. © 1979, American Chemical Society. All rights reserved.