Arene-ruthenium(II) complexes with hydrophilic P-donor ligands: versatile catalysts in aqueous media

In the last few years there has been increasing interest in the use of water as a reaction medium for catalysis, and therefore in designing water-soluble transition-metal catalysts. Half-sandwich (eta(6)-arene)-ruthenium(II) complexes are a versatile and well-known family of ruthenium compounds that exhibit a rich catalytic and coordination chemistry. This Perspective article focuses on the catalytic applications in aqueous media of (eta(6)-arene)-ruthenium(II) complexes containing water-soluble phosphines, and related hydrophilic P-donor ligands.