Study Of Synthese Structures And Luminescent Properties Of Bis(Imino)Pyridyl Cu(Ⅱ) Comlexes

Synthesis and the properties research of organic blue luminescence material is always hot research in luminescent material domain, but its stability, brightness has not solved yet. Therefore it's challenging to designs and synthesizes organic luminescent material with highly effective blue light via using the controllability of metallic ion and the ligand. The present paper is for the purpose of designing synthesizes five bis(iminoalkyl)pyridine CuII complexes, the structure and luminescence properties of these complexes were determined.2,6-bis(iminoalkyl)pyridine ligands 2,6-bis[1-(phenylimino)ethyl]pyridine (L1), 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine (L2), 2,6-bis[1-(2-methylphenyl-imino)ethyl]pyridine (L3), 2,6-bis[1-(4-methylphenylimino)ethyl]- pyridine (L4), 2,6-bis[1-(2,6-diethylphenylimino)ethyl]pyridine (L5) were synthesized. The syntheses technics of five ligands have been improved as literature reported and the yield increased to 85% above. The structure of five ligands have been characterized by Elemental analyses, NMR, IR spectra etc, and the luminescence properties were determined by UV-Vis and emission spectra. They all have blue fluorescent at room temperature in dichloromethane solution. The emission maximum peak for five ligands is 369, 386, 378, 380 and 382 nm, the order of ligand emission spectrum energy is L1 > L5 > L3≈L4 > L2.Five copper complexes of these ligands were prepared by reaction of CuCl2 with a stoichiometric amount of the corresponding 2,6-bis(iminoalkyl)pyridine ligand in acetonitrile. All ligands have been characterized by Elemental analyses, NMR, IR spectra etc. All copper complexes were obtained as crystals, the crystal structures were determined by X-ray singl-crystal diffraction. Five complexes can be best described as distorted trigonal-bipyramidal with metal copper as the central. The luminescence properties of five complexes were studied, they all have blue fluorescent at room temperature in dichloromethane solution. The emission maximum peak for five ligands is 466, 494, 478, 479 and 486 nm. The order of emission spectrum energy is Cu1 > Cu3≈Cu4 > Cu5 > Cu2, the metal centers played a key role in five preparations to enhancing fluorescence emission of the ligandπ*→π.