Dinuclear gold(i) complexes of bridging bidentate carbene ligands: synthesis, structure and spectroscopic characterisation

Citations Over TimeTop 10% of 2004 papers

Abstract

Eight dinuclear Au(i)-carbene complexes have been synthesized from various imidazolium-linked cyclophanes and related acyclic bis(imidazolium) salts, by treatment of the imidazolium salts with [Au(i)(SMe(2))Cl] in the presence of a carboxylate base. Single crystal structural studies showed that the Au(i)-carbene compounds contain dinuclear (AuL)(2) cations in which a pair of gold(i) centres are linked by a pair of bridging dicarbenoid ligands. Interestingly, the structural studies revealed short AuAu contacts of 3.0485(3)[Angstrom] and 3.5425(6)[Angstrom] in two of these complexes. NMR studies showed that the (AuL)(2) cations constructed from the cyclophane-based ligands retain a relatively rigid structure in solution, whilst those of the non-cyclophane ligand systems are fluxional in solution. The electronic absorption and emission spectra of the complexes in solution at room temperature were recorded and the complex with the shortest AuAu contact was found to emit intensely at 400 nm and more weakly at 780 nm upon excitation at 260 nm. The compounds with longer AuAu separations were not emissive under these conditions.

Related Papers

• → Carboxylate Binding Modes in Zinc Proteins: A Theoretical Study(1999)126 cited
• → Synthesis and structural characterization of a silver complex of a mixed-donor N-heterocyclic carbene linked cyclophane(2001)99 cited
• → An nmr study of gadol inium (iii) hydroxycarboxtlate complexes in aqueous medium using gd(iii) induced 13c relaxation rate enhancements(1986)29 cited
• → Synthesis, characterization and cytotoxic assay on human liver carcinoma cells (HepG2) of organodistannoxane dimer complexes derived from alkylaminobenzoic acids(2011)2 cited
• → A novel monomeric manganese(ii) carboxylate. preparation and structure of Na2[Mn(Me3NCH2CH2CO2)4(H2O)2](ClO4)4 · 4H2O(1996)2 cited