Metal ion-coupled electron transfer of a nonheme oxoiron(IV) complex: Remarkable enhancement of electron-transfer rates by Sc3+

Abstract

Rates of electron transfer from a series of one-electron reductants to a nonheme oxoiron(IV) complex, [(N4Py)FeIV(O)]2+, are enhanced as much as 108-fold by addition of metal ions such as Sc3+, Zn2+, Mg2+, and Ca2+; the metal ion effect follows the Lewis acidity of metal ions. The one-electron reduction potential of [(N4Py)FeIV(O)]2+ is shifted to a positive direction by 0.84 V in the presence of Sc3+ ion (0.20 M). © 2011 American Chemical Society.