ИСТИНА

Catalysts for olefm polymerization play key roles in industry．These catalysts have been developed from Zeigler-Natta catalysts through metallocene catalysts to constrained geometry catalysts (CGCs) and non—metallocene catalysts. Among these types of catalysts, CGCs are thought to be one of the most prospective ones what attracts many researchers because of their specific characteristics in olefin polymerization. Development of novel CGCs nOW becomes one of the most active strategies in olefm polymerization catalysts design. The initial idea of this dissertation was, first, to find synthetic approaces to side-chain functionalized cyclopentadiene-type (Cp-type) ligands by reactions of lithiated imidazoles with fulvenes and, second, apply new ligands for preparation of the Group 4 transition metal complexes as the strightforward precursors of olefin polymerization catalysts. The catalytic systems derived from these designed catalyst precursors are thought to have high activity, require less methylalumoxane (MAO), and produce polyolefins with narrow molecular weight distribution. This dissertation focuses on designing, synthesis, structural characterization, and polymerization performance test of the ligand precursors of question． Among the various N-protecting groups, dialkoxymethyl one satisfied the requirements of the ligand synthesis the best. At this step, a new compound, 2-methyl-N-diethoxylmethylimidazole, has been prepared. The further steps of chemical transformations involved lithiation of 1-methylimidazole or 1-diethoxylmethylimidazole and reactions of the lithio-intermediates with appropriate fulvenes. Six new Cp-(C1 or C2-link)-(2-imidazolyl) ligands were synthesized. All compounds within this research work were characterized by 1H and 13C{1H} NMR, GC—MS (organic materials), elemental and X-ray diffraction analyses. The prepared imidazolyl side—chain funcfionalized cyclopentadienyl type ligands were converted into the Group 4 metal complexes via their lithium derivatives or by direct reactions of their CH—forms with tetrakis(diethylamides) of titanium. Two titanium complexes were studied in details．