Rigid chelating dicarbene ligands based on naphthyridine-fused bisimidazolium salts

Abstract Naphthyridine-fused bisimidazolium salts were designed and synthesized for the first time. The study of the Cu(II) and Pd(II) complexes demonstrated that the deprotonated dicarbene ligands are rigid chelating C,C-ligands with strong electron-donating ability in analogy with the classic phenanthroline N,N-ligands.