| Nowadays, polyolefins are among the most demanded material in plastics industry. Catalysts for polymerization is the most critical factors for development of polyolefin material. Researches on metallocene catalysis present one of the growth points in the field of polymerization catalysis and have broad prospects. The first part of the work reports series of synthesis of1-methyl imidazole side chain functionalized indenyl ligands and their application in the Group4transition metal organochemistry.Starting ligands,2-[2-(1H-inden-3-yl)-2-pheny1ethyl]-1-methy1-1H-imidazole (4a) and2-[2-(1H-inden-3-yl)-2-diphenylethyl]-1-methy1-1H-imidazole (4b) were prepared starting from (1’Z-,1’E-)-1-phenylmethylene-1H-indene and/or1-(diphenylmethylene)-1H-indene and2-CH3-lithiated1,2-dimethylimidazole. Ligands4a and4b were fully characterized by1H and13C{1H}NMR spectroscopy. Titanium and zirconium complexes were prepared by two different synthetic routes:via a monolithiated ligand (5a or5b) or via treatment of the ligand in its CH-acid form with M(NEt2)4(M=Ti or Zr). While the latter approach was proved to be ineffective, salts5a and5b were successfully prepared. Subsequent reactions of5a and5b with either Me3SiCl and/or Me3SnCl afforded the desired silylation products6a,6b and stannylation products6a’,6b’Further reaction with TiCl4and ZrCl4allows to prepare the target complexes despite final purification of these complexes still meets some problems.The second part of the work concerns studies of the1,1-carboboration reaction of terminal alkynes (t-butylacetylene and phenylacetylene) B(C6F5)3/stetrically hindered amine Frustrated Lewis Pairs (FLP-s). The related1,1-carboboration products9a and10a were characterized by means of NMR spectroscopy. Both9a and10a present mixtures of Z-and E-isomers. The full assignment of the signals in the NMR spectra was done on the basis of DFT-computational prediction of the spectral parameters for Dihydroborole products of9a and B(C6F5)3.Treatment of9a with either n-or t-BuNH2affords classical N→B Lewis acid-base adducts9b,9c which were characterized by1H-NMR spectroscopy and X-Ray diffraction analysis. Meanwhile, reactions of9a with bulkier diphenylamine and2,2,6,6tetramethylpiperidine (TMP) failed. NMR monitoring of the reaction mixtures of9a and diethylamine and/or diisopropylamine reveals the sings of adducts formation, however, at the moment the related products have not been isolated yet. |
