Synthesis and Properties of Ring Complexes Containging N, N-or N, O-bidentate Ligands

Exploring the syntheses of novel structural complexes, studying their physical andchemical properties as well as their applications is the central motif of coordinationchemistry. Cyclic complexes in coordination compounds have become a very importantclass of compounds. Stable ring complexes can be synthesized by design and selection ofsuitable ligands, central atom and experiment conditions. Ligands containging N, N-or N,O-bidentate have similar structures. The use of these ligands in coordination chemistry hasattracted much attention for several reasons: first, they can be easily synthesized in highyields from readily available starting materials; second, the electronic and steric propertiesof coordination complexes containing N, N-or N, O ligands can be readily tuned byaltering the substituents; third, binding modes to the central atom are virious. The study ofthese complexes is one of the most widely investigated areas of modern main groupchemistry. Four cyclic compounds with N, N-or N, O-bidentate ligands were synthesizedand characterized by single-crystal X-ray diffraction structural analysis,1H NMR, IRspectra, elemental analysis, thermal analysis, UV-vis absorption spectra and fluorescentspectra properties.The synthesis, crystal structure, stability and properties of a series of aluminumcomplexes with Schiff base ligands were studied. The reaction of trimethylaluminum with asalen ligand afforded an one-dimensional structure of an Aluminum coordinationcompound in the crystal state. Comparing with the organic polymer, this type of aluminumcentered macromolecular structure is very rare. Trimethylaluminum as a Lewis acid(electron pair acceptor) reaction with Schiff base ligand, forming the macromolecule withan infinite [C–N–Al–(μ-O-)2–Al–N–C]nchain. It is great significance for the study ofmetal-organic chemical compounds in macromolecular. The reaction of triisobutylaluminium with a salen ligand afforded a structure in the crystal state with pentacoordinatealuminum. X-ray diffraction structures show that compound is a symmetrical structure,which makes the structure framework more stable at the room temperature.With the aim to further investigate the application in silicon and phosphoruscomplexes, two new kind compounds with amine bridged bis(phenol)s ligand weresynthesized and characterized. The reaction of triethylamine with an amine bridgedbis(phenol)s ligand, forming a stable ten-membered ring complexe withdiphenyldichlorosilane. X-ray diffraction structures show that compound is a symmetrical structure with the silicon atom in the center, which makes the structure framework morestable at the room temperature. Compound has good thermal stability through thermalanalyses. The study of fluorescent spectra properties shows that the compound exhibitsstrong fluorescence under ultraviolet light. So they appear to be good candidates for novelpotential organic-inorganic photoactive materials. The reaction of dichlorophenylphosphinewith an amine bridged bis(phenol)s ligand afforded a stable ring complexe structure of anphosphorus coordination compound in the crystal state.