Novel monophosphido-bridged diruthenium complexes: Efficient preparative method and catalytic activity toward reactions of propargylic alcohols with aromatic compounds

Reactions of a chloride-bridged diruthenium (III) complex with (dialkylphosphino)trimethylsilans afford novel monophosphido-bridged diruthenium complexes, which are further transformed into the corresponding cationic complexes by treatment with silver trifluoromethanesulfonate. The dimethylphosphido-bridged complex is found to work as a dual catalyst toward the redox isomerization of propargylic alcohols to alpha,beta-unsaturated ketones and sequential Friedel-Crafts reactions with heteroaromatic compounds.