Metal-to-metal transfer of vinyl ligands: ruthenium-catalysed synthesis of vinylmercury compounds

Abstract

Vinyl ligands are readily transferred from ruthenium(II) to mercury(II), giving mono- or di-vinyl mercury complexes, depending on the vinyl ligand and the reaction conditions used. In conjunction with steps involving aryl ligand transfer from mercury to ruthenium and insertion of MeO₂CCCCO₂Me into the ruthenium–aryl bond, this constitutes a ruthenium-catalysed route for the conversion of [HgR₂](R = aryl) into [Hg{C(CO₂Me)C(CO₂Me)R}R] and [Hg{C(CO₂Me)C(CO₂Me)R}₂], with alkyne insertion as the rate-limiting step. The mechanism of transfer alters according to the nature of the vinyl ligand. Reaction of [Ru(CO)₂{C(CO₂Me)C(CO₂Me)H}Cl(PMe₂Ph)₂] with HgCl₂ does not lead to vinyl transfer: the product was characterized by X-ray crystallography as [[graphic omitted]Me)H}(PMe₂Ph)₂][HgCl₃].