Electrochemical reduction of sym- and unsym-benzoferroles. The generation of stable radical anion and dianion species

Abstract

Voltammetric investigations on sym- and unsym-benzoferroles showed both are reduced in two reversible one-electron steps. While sym-benzoferrole undergoes the two reduction processes at the same potential giving a stable dianion, the reduction potentials for unsym-benzoferrole are separated yielding a stable radical anion while the dianion undergoes a relatively fast decomposition. Interpretation of this behavior is made by a comparison with ferrole itself and a correlation of electrochemical, spectroscopic and MO calculations.