Mono- and bimetallic rhodium(I) complexes supported by new C2-Symmetric bis-N-heterocyclic carbene ligands:: Metalation via C=C bond cleavage under mild conditions

The first example of a tethered chiral enetetramine is presented along with its mild metalation with Rh(I) sources to produce chiral, bis-N-heterocyclic carbene complexes. Subtle steric effects determine whether an enetetramine is accessible versus a free biscarbene.