Substituted o-quinodimethane complexes of ruthenium(0)
Abstract
Reactions of [RuCl2L4](L = PMe3 or PMePh2) with the lithium salts of 1,2,3-trimethyl-, 1,2,3,4-tetramethyl-, or 1,2,4,5-tetramethyl-benzene lead to complexes which contain co-ordinated methyl substituted o-xylidene moieties. Spectroscopic studies confirm the metal-ligand interaction as intermediate between (σ2,π) and (π2) and the o-xylidene moieties can be better described as methyl substituted o-quinodimethanes. By contrast reaction of the lithium salt of o-xylene with [RuCl2{P(OPh)3}4] gives the o-metallated compound [[graphic omitted]OPh)2){P(OPh)3}3] whilst reaction of the lithium salt of 3,4-dimethylanisole with [RuCl2(PMe3)4] gives [[graphic omitted]H2Me2)(PMe3)4] with binding through a phenyl carbon atom. The structures of these complexes have been assigned by spectroscopic means.