Studies of Zinc(II), Copper(II) and Ferrous(II) Complexes Having a Tridentate [2,2′:6′,2"-Terpyridine]-4′-carboxylate Ligand

Three mononuclear complexes, formulated as [ZnL2]center dot 4H(2)O (1), [CuL2]center dot 4H(2)O (2) and [FeL2]center dot 4H(2)O (3) (LH=[2,2':6',2 ''-terpyridine]-4'-carboxylic acid),have been synthesized under the solvothermal conditions and characterized by elemental analysis, IR spectral, and single-crystal and powder X-ray diffraction methods. Complexes 1 similar to 3 are isomorphous structures and they crystallize in the tetragonal space group I (4) over bar 2d. The ligand shows a tridentate chelating mode where the deprotonated carboxylate unit is free of coordinative bond. Three-dimensional supramolecular networks are observed in 1 similar to 3, which are sustained by pi-pi stacking and hydrogen bonding interactions. In addition, the solid-state luminescence spectrum of zinc(I) complex 1 reveals strong blue photoluminescence at room temperature. CCDC: 925947, 1; 925948, 2; 925949, 3.