Coordination compounds of titanium (IV) and 2-hydroxymethyl-phenol derivatives: Their synthesis, structure and catalytic activity in ethylene and 1-hexene polymerization

Olefin polymerization behavior of titanium(IV) alkoxo complexes with fluorinated diolate ligands: The impact of the chelate ring size and the nature of organoaluminum compounds

“…[22][23][24] The introduction of a stable bis-(CF 3 )-carbinol fragment into various phenols allowed us to obtain a series of highly active in olefin (co) polymerization titanium complexes. [25][26][27][28] The successful use of ligands containing bis-(CF 3 )-carbinol fragment to prepare highly active olefin polymerization catalysts has been provided previously. [29,30] The introduction of electron-withdrawing fluorine atoms into the structure of S C H E M E 1 Synthesis of ligands 2a-c and Ti(IV) diolate complexes 3a-d diolate ligands leads to a significant increase in the acidity of hydroxyl groups, which should facilitate the process of the complex synthesis and increases its stability.…”

Impact of the method of Mg 2+ cation introducing into the titanium post-metallocene catalytic system on their activity

“…In the presence of conventional organoaluminum activators -Me 3 Al, Et 3 Al, i-Bu 3 Al, Et 2 AlCl and MAO, this complex did not show catalytic activity in the polymerization of ethylene, as was already noted. [7,28] Moreover, adding magnesium chloride to these catalytic systems also does not lead to its activation. However, mechanochemical activation of anhydrous magnesium chloride, obtained by dehydration of its crystal hydrate in a mixture with ammonium chloride, in a ball mill for 5 hours in absolute toluene medium and in the presence of Et 3 Al somewhat changes this previously obtained result.…”

“…Among the vast majority of various post-metallocene polymerization catalysts developed over the past decades, [1][2][3][4][5][6] perhaps the least studied are complexes of group 4 metals with (O^O) type ligands, in which one or both hydroxyl groups are not phenolic, but alcoholic. These pre-catalysts have shown fairly high e ciency in the synthesis of ultra-high molecular weight polyethylene (UHMWPE), [7][8][9][10][11][12][13] a promising structural material of industrial interest. [14][15][16] However, the large molecular weight of the polymer and the presence of a three-dimensional network of macromolecule entanglements determines the very high viscosity of its melt, which greatly complicates its processing.…”

“…The above-mentioned Ti(IV) complexes with O^O-type ligands are capable of producing dis-UHMWPE. [7][8][9][10][11][12][13] However, these pre-catalysts have their own speci cs, which…”

Crystal structure of 2,4-di-tert-butyl-6-(hydroxymethyl)phenol

“…CH 2 group of (I) have been replaced by CF 3 /C 6 F 5 groups to coordinate to titanium(IV) centres [ZUNWOW and ZUNWUC (Tuskaev et al, 2015); XEMBAU and XEMREY (Solov'ev et al, 2011)]. ZUNWOW is noteworthy because fluorine also acts as a ligand to a coordinated lithium ion.…”