DNA Mismatch Recognition by a Hexacoordinate Silicon Sandwich–Ruthenium Hybrid Complex

The diastereoselective synthesis of two dinuclear Ru–Si complexes is reported, in which silicon­(IV) is coordinated in an octahedral fashion by two 1,10-phenanthrolines and one 4,5-pyrenediolato ligand and additionally η6-coordinated to a (η5-pentamethylcyclopentadienyl)­ruthenium­(II) moiety through one fused benzene ring of the pyrene ligand. One of these Ru–Si hybrid complexes was found to selectively stabilize DNA duplexes that contain cytosine–cytosine or cytosine–thymine mismatches, and it is proposed that this occurs by a novel dual insertion/intercalation binding mode in which the entire ruthenium sandwich unit is introduced into the DNA π-stacking at the site of the DNA mismatch.