Bis-N-heterocyclic carbene ruthenium(II) carbonyl complexes: Synthesis, structural characterization and catalytic activities in transfer hydrogenation of ketones

In this contribution, the synthesis and characterization of eight ruthenium(II) carbonyl complexes supported by chelating alkane-bridged bis-N-heterocyclic carbene ligands are reported. The products obtained are analyzed using infrared and NMR spectroscopies. The molecular structures of four metal complexes were determined by X-ray crystallography, which exhibit the six-coordinate octahedral geometry with two carbene carbon atoms from the bidentate Bi-NHCs, two carbonyl groups and two chlorine atoms in the trans(Cl)–cis(CO) configuration. All these complexes show catalytic activities in transfer hydrogenation of ketones.

Graphical abstractA series of ruthenium(II) carbonyl complexes bearing bis-N-heterocyclic carbene have been synthesized and characterized. The X-ray structure determination of the four complexes showed the octahedral geometry with a chelating coordination of the bis-NHC. They have been proved to be active catalysts in transfer hydrogenation.Figure optionsDownload full-size imageDownload as PowerPoint slide