Group 11 -Terphenyl Complexes Featuring Metallophilic Interactions.

A series of group 11 -terphenyl complexes have been synthesized via a metathesis reaction from the iron(II) complexes (2,6-MesCH)Fe and (2,6-XylCH)Fe (Mes = 2,4,6-MeCH; Xyl = 2,6-MeCH). [2,6-MesCHM] (, M = Cu; , M = Ag; , M = Au) and [2,6-XylCHM] (, M = Cu; , M = Ag) are dimeric in the solid state, although different geometries are observed depending on the ligand. These complexes feature short metal-metal distances in the expected range for metallophilic interactions. While - are readily isolated using this metathetical route, the gold complex is unstable in solution at ambient temperatures and has only been obtained in low yield from the decomposition of (2,6-MesCH)Au·SMe (). NMR spectroscopic measurements, including diffusion-ordered spectroscopy, suggest that - remain dimeric in a benzene- solution. The metal-metal interactions have been examined computationally using the Quantum Theory of Atoms in Molecules and by an energy decomposition analysis employing natural orbitals for chemical valence.