Reactivity of co-ordinated ligands. Part XVIII. Cationic ruthenium(II) and osmium(II) complexes by electrophilic attack on a π-allyl ligand

Abstract

Monocationic ruthenium(II) and osmium(II) complexes containing labile acetonitrile ligands have been prepared by electrophilic attack on a π-allyl ligand in M (diene)(π-allyl), species (M = Ru or OS, diene = norbornadiene or cyclo-octa-1,5-diene). The acetonitrile ligands may be replaced by Group VA chelating ligands. The allyl ligand in the monocationic species is also attacked by electrophiles to yield dicationic complexes. The stereospecific exchange of acetonitrile ligands in the cationic species is described. N.m.r. data, including a reinterpretation of those for the Ru(diene)(π-allyl)₂ species, are presented and discussed.