Metal–Arene Interactions in Dialkylbiarylphosphane Complexes of Copper, Silver, and Gold

Dialkylbiphenylphosphane-Au(I) complexes exhibit only weak metal-arene interactions with the covering arene ring. However, the contacts in isoleptic Ag(I) and Cu(I) complexes are shorter than the limiting values of 3.03 A (Ag(I)) and 2.83 A (Cu(I)). Strong metal-arene interactions were also found in the two Ag(I) aquo complexes and in two acetonitrile--Cu(I) complexes with dialkylbiphenylphosphane ligands. Arene-Ag(I) complexes with these bulky phosphane ligands show the strongest Ag(I)--arene bonds known.