Synthesis and Characterization of a Pd(II)-Complex Bearing a Naphthalene-Based Macrocyclic Tetra <i>N</i>‑Heterocyclic Ligand

We report the synthesis of a novel macrocyclic salt containing four imidazolium units tethered by alternating ethylene and naphthalene units. The salt metalates Pd(II), resulting in a macrocyclic tetra N-heterocyclic carbene (NHC) ligand. To investigate the fluxionality of this complex as a result of its macrocyclic nature, we synthesized a related Pd(II) complex with two chelating NHCs for comparative analysis by 1H NMR spectroscopy.