Two Different, Metal-Dependent Coordination Modes of a Dicarbene Ligand
journal contributionposted on 2013-11-11, 00:00 authored by Ramananda Maity, Arnab Rit, Christian Schulte to Brinke, Jutta Kösters, F. Ekkehardt Hahn
The bisimidazolium salt H2-1(PF6)2 featuring a bridging 1,4-phenylene group reacts with 0.5 equiv of [PdCl(allyl)]2 in the presence of Cs2CO3 to give the dinuclear complex (PF6)2, whereas the reaction of the same bisimidazolium salt with 0.5 equiv of [Ir(Cl)2(Cp*)]2 yields the mononuclear orthometalated complex PF6 with one remaining imidazolium unit. The unreacted imidazolium group in complex PF6, however, can also be metalated with RhIII to yield the doubly orthometalated heterobimetallic complex . In complex , each MIII center (M = IrIII and RhIII) is coordinated by one NHC unit and orthometalates the central aryl ring of the ligand.