Ferrocene-appended anionic N-heterocyclic carbene and its complex with silver(I): Synthesis, structure and catalytic evaluation

A binuclear Ag(I) complex (1) bridged by two anionic N-heterocyclic carbene (NHC) ligands ferrocenoyl(1-mesitylimidazol-2-ylidine-3-yl)amide is synthesized. X-ray structure reveals a [Ag· · ·Ag] core spanned by two ligands, each bridging two metals through carbene carbon and amido nitrogen. The neutral complex (1) is highly soluble in a variety of organic solvents and is thermally stable. Complex (1) efficiently catalyses aniline-mediated synthesis of substituted quinolines from 2-aminobenzaldehyde and terminal alkynes.