Luminescence Of 1,8 - Naphthyridine Derivatives Cu (I) Complexes Of Design, Synthesis And Nature Study

1, 8-naphthyridines, which show good biological activities and are mainly used to medicines, have attracted boffin's attention for their good fluorescence properties and coordinated characters. Recently, polypyridine compounds charactered by conjugate π-electron structure and the luminescent complexes formed by polypyridine ligands with transition metal have gained a lot of attention for their potential applied as the sensor materials, probs and optical materials. In this paper, a new series of luminescent compounds based on 1, 8-naphthyridine unit have been designed and synthesized. The structures of the compounds are characterized by IR, ~1H NMR, MS. The spectral properties for them are investigated in different solvents and solid state. The impact of varying polarity solvent, pH and ionic species such as Zn2+, Cu+ were also studied on absorption and emission spectra. The structure of the complex {[Cu4(C2oH18N5)2(dcpm)2](BF4)2} is determined by X-ray diffraction anslysis and its spectral properties is investigated. The results are as follows:(1) Three new styryl-l,8-naphthyridine-ol compounds have been designed and synthesized. Their structures and spectral properties have been determined and performed. The compounds with different electron donating or withdrawing substitute display different photophysical properties. The changes of substitutes' character have great influence on the luminescence when they are coordinated to metals , which can be used to distinguish different metal ions.(2) A symmetrical sawtooth imine compound containing 1,8-naphthyridine has been synthesized. Its structures and properties have been determined and investigated. The compounds have intense luminescence and the emissive maximum is red-shifted with the increase of solvent polar. Upon addition of H+ and metal ions, particularly Zn2+, the absorption and emission spectra of the compounds process great changes. The high selectivity can be applied as fluorescence sensors for H+ and Zn .(3) Apolynuclear complex of copper(I) with bis(5,7-dimethyl-l,8-naphthyridin -2-yl)amine and dcpm (Bis(dicyclohexylphosphino)methane) has been designed and synthesized. Its structure was determined by X-ray crystal analysis. The salmon pink complex has symmetrical configuration and is stable at room temperature. Short copper-copper distance ( 2.61A ) was observed in the crystal structure. Its photophysical properties have been performed under different conditions.