An Extended Metal Chain with the 2,7‐Bis(dipyridyldiamino)‐1,8‐naphthyridine (H4bdpdany) Ligand – The Longest Even‐Numbered Metal Chain Complex

A decanickel extended metal atom chain (EMAC) complex with a new pyridyl- and naphthyridyl-modulated ligand (H4bdpdany) was synthesized. Analysis of the crystal structure of complex [Ni10(μ10-bdpdany)4(NCS)2](PF6)2 (1) shows that all of the bdpdany4– ligands bind the metal in an all-syn conformation, and structural data reveals short Ni···Ni distances in the range 2.36–2.23 A. Temperature-dependent magnetic measurements performed on two independent high-spin nickel(II) ions of complex [Ni10(μ10-bdpdany)4(NCS)2](PF6)2 (1) demonstrate that the metal chain is antiferromagnetic. The longer distance between the two terminal high-spin nickel(II) ions relative to those in tetranickel and hexanickel strings causes a decrease in the magnitude of the antiferromagnetic interaction.