Synthesis, Characterization and Fluorescence Property of a New Zinc(II) Complex Based on 2,6-Bis(imino)pyridyl Ligand

Abstract

A new zinc(II) complex [Zn(L1)Cl2]‧CH3CN‧1/2H2O (complex 1), where L1 stands for 2,6-Bis{[(2-ethylphenyl)imino]ethyl}pyridine, has been synthesized and characterized. Both the crystal structures of complex 1 and L1 have been determined by single-crystal X-ray diffraction. L1 crystallizes in monoclinic system P21/n space group, with a = 7.7165(5) A, b = 9.1139(7) A, c = 30.535(2) A, β = 96.037(2)° and Z = 4. Complex 1 crystallizes in the orthorhombic system, space group Pbca, and its crystallographic data are a = 14.0520(9) A, b = 14.5780(11) A, c = 26.3450(17) A, α = β = γ = 90°, and Z = 8. In complex 1, Zn1 atom is five-coordinated with a trigonal bipyramidal geometry. L1 acts as a tridentate ligand and coordinated to Zn1 with three nitrogen atoms. A two-dimensional supermolecular network is formed by hydrogen bonds, in which acetonitrile and water solvent molecules play an important role. The luminescent properties of L1 and complex 1 were investigated in the solid state. The results indicate that when coordinated with Zn atom, the fluorescence intensity of complex 1 increases accompanied by a blue-shift, which can be attributed to metal perturbed π–π* intraligand fluorescence. The single crystals of 2,6-Bis{[(2-ethylphenyl)imino]ethyl}pyridine (L1) and it’s Zinc(II) complex [Zn(L1)Cl2]‧CH3CN‧1/2H2O (1) were determined. In the crystal structure of complex 1, the acetonitrile and water solvent molecules play great role in the formation of hydrogen bonds, forming a two-dimensional supermolecular network structure.