Imidazole Side Chain Imine Ligand Complexes Synthesis And Characterization

Synthetic polymers play an important role in our society, affecting nearly every aspect of modern life. The ubiquitous nature of these materials is a result of years of collaboration between researchers in both fundamental and applied areas of various disciplines. It finds the yield in economic routes to materials that meet customer needs. The key problem of production of polyolefins which exhibit the desired particular properties lays the area of catalysts, and, thus, that the development of new specific catalytic systems is top essential for the entire polymer industry.This thesis presents the further development of the investigations which has been carried out by our research team for several years and within which various imidazole side chain functionalized cyclopentadienyl ligands and their corresponding titanium and zirconium complexes have been prepared and studied. Being a five-membered heterocycle containing two nitrogen atoms, imidazole moiety possesses rather specific reactivities. By means of linking of an imino [and cyclopentadienyl (Cp)] groups as a side chains to the imidazolyl fragment we have synthesized a series of novel Cp or non-Cpl ligands and the Group 4 transition metal complexes derived from them.At the beginning of this research, an attempt to prepare imidazole side chain functionalized ligand containing both Cp-and imino-functions,2-cyclopenta-1,3-dien-1-yl-N-[(1E)-1H-imidazol-2-ylmethylene]ethanamine (5a) and 2-{(E)-N-[2-(1H-inden-3-yl)ethyl] iminomethyl}-1H-imidazole (5b), was undertaken. Two different synthetic approaches to the ligand 5a have been tried. However, instead of the target ligand we obtained another amino-compounds which possess a fulvene-type structure (5a'). Further we have successfully developed the synthetic approaches to the target ligand 5b, with its structure confirmed by NMR, GC-MS and X-ray diffraction analysis methods. In addition, we also tried to synthesize imidazole side chain functionalized non-cyclopentadienyl imino-group containing ligands, N-benzyl-N-[(1E)-1H-imidazol-2-ylmethylene]amine (5c) and N-[(1E)-1H-imidazol-2-yl-methylene]-N-methylamine (5d), with both of them also adequately characterized.The next step of the present investigation was preparation of the Ti(IV) and Zr(IV) complexes based on these ligands mentioned above. For instance, crystal and molecular structure of the novel rac-(OC-6-33)-bis(dethylamido)bis[2-(N-phenylmethyliminomethyl)-1H-imidazolido-κN1,N1,]titanium(Ⅳ) (7c1) was established by X-ray diffraction analysis and 1H and 13C{1H} NMR spectroscopy.This complex is expected to be a prospective catalyst precursor for the olefin polymerization and will be used as one of the starting points for the further investigations in our research team.