Synthesis And Characterization Of Multi-dental Organic Ligands Containing Nitrogen And Phosphorus And Their Complexes

The linear chain complexes containing poly-nuclear metal atom, can be considered as a metal string that is cut from bulk metal by organic ligand. This kind of complexes is becoming great interesting because of their unique structure, polynuclear metal-metal bonding and potential application as molecular wires. In the past ten years, oligo-2-aminopyridines have been successfully to construct series of linear chain complexes. The longest chain complex had been reported in 2000, in which linear nonanickel atoms are connected through metal-metal bond. The lenghth is 1.8?. Compared to high-valent metal complexes, the metals at low-oxidation state, especially the metals possessing d10 electron configuration, have tendency to aggregate to form clusters, which exhibit unusal photochemical, electrochemical and catalytic properties. Ligand containing N atom and P atom usually be used to study the interaction between two different metals. However, few were seen upon this kind of ligand used to construct metal chain complexes, and study on low-valent metal chain complex was very limited.In this paper, we prepared a series of polydentate pyridylphosphine ligands that contained nitrogen and phosphorus coordinative atoms and attempted to synthesize polyphosphine ligand with organo-metallic method. In addition, we used those ligands to synthesis linear chain complexes containing poly-nuclear metal through self-assembly from point of view of molecular architecture. The model complex was synthesized. The products were characterized with FT-IR, UV-vis and 1HNMR spectra.During our synthetic work, the yield was higher than those reported in literature in course of synthesis 2-pyridyldiphenylphosphine and bis (2-pyridylphenylphosphino) methane by organo-metallic chemistry method. The reaction time was shortened. It simplified the manipulation steps, and became more convenient for separating and purifying the products. Farther more, the novel pentadenate bis [2-(diphenyl-phosphino)- 6-pyidyl]phenylphosphine ligand were synthesized. The possibly coordination pattern of complexes containing metal chain supported by those ligands was discussed. Another essential part of this thesis was the investigation of complexes synthesized by those ligands. For the pyridylphosphine ligand, the coordinative property is different for the hard nitrogen atom and the soft phosphorus atom. Therefore, several mononuclear complexes containing Pd(II) were synthesized by pyridylphosphine ligand with P atom coordinated. They were connected into a trinuclear linear complex by Cu(I) which coordinated to uncompleted N atom. Linear multinuclear complexes were systematically studied through self-assembled by those mononuclear units based on model complexes. The investigation results would be of great significance for the development of metal chain complexes and it would afford theoretic foundation for designing molecular wire and low-dimension functional material.