Advances in the coordination chemistry of [M(CN)(5)L](n-) ions (M = Fe, Ru, Os)

New developments m the synthesis, crystal and molecular structure, spectros copy and kinetic properties of the [M(CN)(5)L](n-) ions (M-II.III = Fe, Ru, Os; L = H2O, NH3, amines, CN-, N-heterocyclic ligands, etc.), performed ov er the last decade, are reviewed. The properties of dinuclear complexes con taining pentacyano-fragments bridged by pyrazine, cyanide or other bridging ligands, are also considered, with emphasis on mixed-valent systems. The i nfluence of the solvent and other medium effects on the electronic structur e, as well as on the modification of the reactivity of L upon coordination is addressed particularly. Some catalytic processes relevant to bioinorgani c chemistry are discussed, involving either ligand oxidation (hydrazine, th iolates) or reduction (nitrosyl). (C) 2001 Elsevier Science B.V. All rights reserved.