The Pivotal Role of Ru-dmso Compounds in the Discovery of Well-Behaved Precursors

This paper is a tribute to the rich chemistry and great versatility of ruthenium-dmso precursors: over the years, from a handful of complexes we prepared literally hundreds of derivatives with all types of ligands, from mono- to poly-dentate, from pure sigma-donors (e.g. NH3) to phosphines and strong pi-acceptors such as CO and NO. This systematic and extensive investigation had a red thread running through it: the identification of compounds that might have functional roles, either because they possess peculiar physical-chemical properties or because they undergo predictable and stereo-controlled substitution reactions, i.e. are well-behaved precursors. From a more fundamental point of view, this systematic investigation led us to get a deeper understanding of the subtle differences in the soft nature of ruthenium and osmium, as well as in the delicate balance between electronic and steric preferences of the dmso ligand and of its remarkable adaptability to the coordination environment.