The Synthesis,Crystalline Structure And Fluorescent Properties Of Zinc And Palladium Complexes With Terpyridine

The research of this thesis mainly includes the following parts:1.According to relevant literatures,a series of terpyridine ligands were synthesized:4’-(o-hydroxy-phenyl)-2,2’:6’,2"-terpyridine(L1),4’-(p-methyl-phenyl)-2,2’:6’,2"-terpyridine(L2),4’-(p-fluoro-phenyl)-2,2’:6’,2"-terpyridine(L3),4’-(p-methysulfonyl-toluene)-2,2’:6’,2"-terpyridine(L4),4’-(p-methoxyphenyl)-2,2’:6’,2"-terpyridine(L5),4’-(m-hydroxy-phenyl)-2,2’:6,2"-terpyridine(L6),4’-(p-hydroxy-phenyl)-2,2’:6’,2"-terpyridine(L7).Five sandwich core zinc complexes were synthesized by reaction of Zn(NO3)2 with ligands L1-L5 by hydrothermal method or organic solvent method:[ZnL12](NO3)2(1),[ZrL22](NO3)2(2),[ZnL32](NO3)2(3),[ZnL42](NO3)2(4)and[ZnL52](NO3)2(5),respectively.The structures of these complexes were characterized by 1H NMR,IR and X-ray diffraction.The results showed:(1)and(4)belong to the monoclinic system.In addition,(2),(3)and(5)belong to the triclinic system.The zinc ion in these complexes are six-coordinated with distorted octahedron geometry.Finally,the fluorescence properties of complexes 1-5 were researched and discussed.The conclusion is that the luminescence of complexes 1-5 in the high-energy region is due to theπ-π*energy level transition of the aromatic ring,and the different ligand substituent is a greatly influence on the conjugation degree of the aromatic ring and electron delocalization range of the system,and thus affects luminous efficiency and intensity.In the low-energy regions,the charge transfer of metal zinc ions to the ligand(MLCT)is the main cause of fluorescence.In this interval,the main effect of substituents on the fluorescence properties of these complexes depend on their ability to feed electricity.The substituent with a strong feeding ability enhances fluorescence,that with a weak feeding ability will weaken the fluorescence,and even quench the fluorescence.2.Three palladium complexes[PdClL1]Cl(6),[PdClL6]Cl(7)and[PdClL7]Cl(8)were by hydrothermally and organically synthesized with PdCl2 and 4’-(o-hydroxy-phenyl)-2,2’:6’,2"-terpyridine(L1),4’-(m-hydroxy-phenyl)-2,2’:6’,2"-terpyridyl(L6),4’-(p-hydroxy-phenyl)-2,2’:6’,2"-terpyridine(L7),respectively.The structures of these complexes were characterized by IR and X-ray diffraction.The results of crystalline structures show that:both[PdClL1]Cl(6)and[PdClL6]Cl(7)belong to monoclinic system.[PdClL7]Cl(8)belongs to rhombohedral system.In addition,the palladium ion in these complexes are four-coordinated with flat-square.Solid fluorescence properties of complexes 6 to 8 were determined and analyzed.It was concluded that the peculiar fluorescence phenomenon may be relates to the unique coordination pattern between the palladium ion with the ligand and the presence of MLCT electron transitions in the complexes,so that the positions of the substituent almost no effect on the fluorescence for palladium complexes.