Silver and gold complexes with a new 1,10-phenanthroline analogue n-heterocyclic carbene: A combined structural, theoretical, and photophysical study

Unusual coordination for gold: An imidazolium salt was synthesized and used as a precursor for an N-heterocyclic carbene, which can be considered as the carbene analogue of 1,10-phenanthroline. Like the diimine congener, this ligand gives luminescent metal complexes. Remarkably, the AuIII complex features a gold atom in an unusual environment: it is surrounded by six donor atoms, two of which interact electrostatically with the Au atom (see figure).