Synthesis and Characterization of a Series of New Luminescent NHC‐Coordinated Au^I–Ag^I Tetra‐ and Polymetallic Complexes Containing Benzoate‐Bridged Ag₂ Dimers

Abstract

Abstract The reaction of [Au(CH 3 impy) 2 ]PF 6 ( 2 ), with substituted silver benzoate salts bearing different halide substituents produced a series of new mixed‐metal species having two different structural motifs. One structural motif contains discrete tetrametallic Ag 2 Au 2 diamond cores, whereas the other motif contains the same tetrametallic diamond core interconnected by benzoate‐bridged silver dimers to form polymers. All the complexes are substitution‐inert and stable both in the solid state as well as in solution. We also report the synthesis of oxidative addition products of [Au(CH 3 impy) 2 ]PF 6 , which were also obtained during our attempts to oxidize the above‐mentioned multimetallic assembly with bromine and iodine. Compounds 3 – 7 are intensely luminescent in frozen acetonitrile solution, but surprisingly no luminescence is observed at room temperature. All the complexes were completely characterized by 1 H, 13 C NMR, electronic absorption, emission spectroscopy, elemental analysis and X‐ray crystallography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)