High-Valent Complexes of Ruthenium and Osmium

Abstract

The study of high-valent complexes of osmium (Os) and ruthenium (Ru), especially those involving multiple bonding to heteroatoms, has greatly expanded during the past decade. Osmium and ruthenium, being distinguished from other elements by the variety of the oxidation states they display in their complexes, have attracted a plethora of study on their coordination chemistry. The chapter focuses on the high oxidation state chemistry of osmium and ruthenium—that is, those complexes with oxidation states of + IV to + VIII. In this review, the materials have been organized according to the formal oxidation states of the metal and the discussions focus mainly on the structural as well as reactivity patterns of these complexes. The chapter discusses those complexes that may reasonably be considered to involve discrete molecular units, having metal–ligand multiple bonding. Polynuclear derivatives, in which the ligand bridges two or more metals, are also mentioned in the chapter. The chapter explains high-valent chemistry of ruthenium coordination complexes with various classes of ligands as comprehensive as possible.