Dinuclear gold(I) and gold(III) complexes involving di(N-heterocyclic carbene) ligands – Synthesis, characterization and DFT studies

•Synthesis of gold(I) and gold(III) complexes bearing bis(NHC) ligands.•Oxidation of gold(I) to gold(III) by bromine.•DFT study on thermodynamic aspects of oxidation of gold(I) to gold(III) by bromine.•Gold(III)/gold(III) complex bearing methylene bridged bis(NHC) ligand.

Some new dinuclear gold(I) and gold(III) complexes containing di(NHC) ligands have been synthesized and characterized. The dinuclear centers were coordinated by methylene, ethylene or propylene bridged di(NHC) ligands bearing alcohol functionalized side arms. The oxidation of the gold(I) to gold(III) have been carried out using bromine. X-ray structure analyses of two dinuclear gold(I) and three dinuclear gold(III) complexes show the solid state structures of these compounds. Thermodynamic aspects of the oxidative additions of bromine to the gold(I) species leading to gold(III) compounds passing by unstable gold(II) intermediates have been studied by DFT calculations.

Graphical abstractDinuclear gold(I) and gold(III) complexes have been synthesized. The dinuclear centers were coordinated by methylene, ethylene or propylene bridged bis(NHC) ligands bearing alcohol functionalized side-arms. Thermodynamic aspects of the additions of bromine to the gold(I) species leading to gold(III) compounds via unstable gold(II) intermediates have been studied by DFT calculations.Figure optionsDownload full-size imageDownload as PowerPoint slide