The Stabilization of Low Oxidation States in σ- Organo Transition Metal Chemistry by Coordinative Lithium Transition Metal Interaction

Abstract

Starting from the well known connection between the accessibility of different oxidation states of the transition metals and the donor-acceptor characteristics of the ligands, synthesis and structural characterization of electron-rich phenyl transition metal complexes are reviewed. To explain the existence of these unusual compounds in accordance with Pauling's principle of electroneutrality, a coordinative interaction of lithium ions with the central transition metal atom has been suggested as a new principle of stabilization of low oxidation states in coordination chemistry.