Ruthenium(II) DMSO complexes with CˆC* cyclometalated phenylimidazol NHC ligands

Displacement of the η6-arene ligand in cyclometalated ruthenium NHC complexes by DMSO selectively leads to a change from a facial to a meridional geometry. The DMSO complexes can serve as starting materials for the synthesis of more complex structures, e.g. by introducing bidentate ligands, as shown for 2,2′-bipyridine.181