New generation of metal string complexes: strengthening metal–metal interaction via naphthyridyl group modulated oligo-α-pyridylamido ligands

Abstract

To design new metal string complexes, several naphthyridyl group modulated oligo-α-pyridylamido ligands have been synthesized in the past five years. Because these ligands are less anionic than pyridylamido ligands, the resulting metal string complexes tend to form reduced mixed-valence [Ni₂(napy)₄]³⁺ dinuclear units which contain a delocalized unpaired electron and thus significantly enhance the conductance of metal string complexes. Furthermore, the asymmetric naphthyridyl group modulated oligo-α-pyridylamido ligands can stabilize the central heteronuclear or charge disproportionational metal frameworks, providing a plausible strategy to build inorganic molecular rectifiers.