Synthesis, Characterization And Catalysis Of The Complexes Bearing N,N,N-Tridetate Anilido-Imine Ligands

In this study, two kinds of novel ligands and fifteen kinds of complexesbased on those mentioned ligands were constructed. All these novelcompounds, including six kinds of aluminum complexes, six kinds zinccomplexes and three kinds of nickel complexes as well, were thoroughlycharacterized by using1H-NMR,13C-NMR, and X-RD spectrometers. Foraluminum and zinc complexes, their catalytic behaviors as initiators of thering-opening polymerization of L-lactide were investigated by designing aseries of experiments, aiming at exposing the mechanism of catalyticpolymerizations. Meanwhile, the structures of the nickel complexes wereprecisely characterized and confirmed by using1H-NMR,13C-NMR and X-RDspectrometers.In chapter3, a series of mononuclear/binuclear aluminum complexesbearing N,N,N-tridentate quinolinylanilido-imine ligands were synthesized andcharacterized. Mononuclear aluminum complexes exhibited trigonalbipyramidal coordination around the metal center, while binuclear complexesshowed that all the aluminum atoms were in a tetrahedral geometry.Analogous monoligated/bisligated zinc complexes were also prepared. Thezinc atoms inmonoligated complexes were in a tetrahedral geometry, while inbisligated complexes, they showed trigonal bipyramidal geometries. The Zncomplexes were efficient initiators for L-lactide ring-opening polymerization inthe presence of benzyl alcohol, and the polymerization could be performed inan immortal manner. With the higher conversion of monomer, the PDI still keptin the range from1.09to1.30, it furthered proved the feature of activepolymerization. Furthermore, the relationship between the monomerconversion and molecular weight of polymers were studied by experimentsand tests. Finally, the mechanisms of the active polymerization were studiedand the active initiators were captured during the progress. In chapter4, three kinds of N,N,N-amine ligands bearing nickel complexeswere obtained by using N,N,N-triamine ligands and NiCl2through lithiumsitu-subtstituened method under low temperatures, and they werecharacterized by NMR spectra. It was found that all these initiators have goodstability to oxygen and water vapor. After confirming the structures of thecomplexes by XRD spectra, we made the conclusion that the three nitrogenatoms and chlorin atom were in the same plane.