The Syntheses, Structure And Properties Study Of 1,2-diaminopropane-based Salen-type Lanthanide Complexes

The salen-type metal complexes have attracted much more attention for their wide application in the fields of biology, catalysis, photoelectricity and magnetism. The preparation of new salen-type metal complexes and study their properties and application are of important significance to design novel functional materials and expand their fields of application.The salen-type ligands derived from propane-1,2-diamine, cyclohexane-1,2- diamine and salicylaldehyde, derivatives were designed and prepared, and the mononuclear lanthanide, 3d-4f dinuclear and 3d-4f-3d′trimetal complexes with these ligands were also synthesized. We studied their crystal structures, properties of catalysis, fluorescence, electric chemistry and magnetism.A series of novel mononuclear lanthanide complexes with the Salen-type ligands were prepared. Further, a new method was used to synthesize Salen-type 3d-4f dinuclear complexes using the mononuclear lanthanide complexes as starting materials. And then, novel one-dimension 3d-4f-3d′trimetal complexes were obtained employing the substitution of the anions and the magnetic studies illuminated that the magnetic interaction between metal ions is ferromagnetic. The synthesis and single crystal structural analysis of three series of complexes expanded the types of salen-type metal complexes and afforded valuable experimental data for exploring new structural models.Moreover, the efficient chiral salen-type ligands were incorporated into lanthanide metal and their salt as catalysts of asymmetric transfer hydrogenation of acetopheneone and derivatives for the first time. Efficient catalytic system was selected. Furthermore, the fluorescent properties of Salen-type lanthanide complexes were studied deeply. Triplet state energy of Salen-type compounds was measured using phosphorescence method and the energy transfer process was discussed. The reason that why Sm(III) and Eu(III) ions can luminescence, but Tb(III) ions were not, was explained from the theory point. Further, stated the reason that why Sm(III) ions can luminescence, but Eu(III) ions were not, when their energy states match well. So, the better luminescence functional materials can be designed and obtained by modifying the structure of ligands.Finally, electrochemical behavior of heterodinuclear Cu-4f complexes were studied by cyclic voltammetry for the first time. The redox potential of heterodinuclear Cu-4f complexes showed significant anodic shift comparing to that of mononuclear copper complex, which indicated the electron accepting ability of Cu(II) ion is markedly increased. This results from the coordination spheres of copper ions becomes more distorted from planar to tetrahedral configuration and enhances their stability and produces anodic shifts in the reduction potentials. Similarly, in the series of heterodinuclear Cu-4f complexes, a tendency of anodic shift was observed. This results from the coordination geometry around Cu(II) ions becomes more distorted regularly from light to heavy lanthanide in the complexes, which was well reflected in the redox behavior of the series of heterodinuclear Cu-4f complexes that a tendency of anodic shift was observed along the direction of lanthanide contraction. These results are of important significance to found relation between structures and properties. It provided valuable information for designing tunable redox potentials of copper complexes constructed by tetradentate (N2O2) salen-type ligands.