Synthesis, structures of half-sandwich titanium complexes with bulky aryloxide ligand and their catalytic performance for olefin polymerization

• Three half-sandwich titanium aryloxides have been synthesized and characterized.
• The molecular structure of complexes 4 and 6 has been determined.
• Complexes 4–6 exhibit good catalytic activity for ethylene polymerization.

Three bulky cyclopentadienyltitanium aryloxide complexes, [Ti(η5-C5Me4Ar)(O-2,6-tBu2C6H3)Cl2], (Ar = C6H5 (4), 4-iPrC6H4 (5), 4-Me3SiC6H4 (6)) have been synthesized from reaction of the corresponding cyclopentadienyltitanium trichloride derivatives with 1 equiv of LiO-2,6-tBu2C6H3. These half-sandwich complexes 4–6 have been characterized by 1H and 13C NMR spectroscopy. The molecular structure of complexes 4 and 6 has been determined by single-crystal X-ray diffraction studies. When activated with iBu3Al and Ph3C+B(C6F5)4−, complexes 4–6 exhibits reasonable catalytic activity for ethylene polymerization, producing moderate molecular weight polyethylenes.

Three half-sandwich titanium complexes, (1-R-2,3,4,5-tetramethyl-cyclopentadienyl) (aryloxo)titanium dichloride complexes, [R = C6H5 (4), 4-iPrC6H4 (5), 4-Me3SiC6H4 (6); Ar = 2, 6-tBu2C6H3] were synthesized and structurally characterized. When activated with AliBu3 and Ph3C+B(C6F5)4−, complexes 4–6 exhibit reasonable catalytic activity for ethylene polymerization, producing moderate molecular weight polyethylene with high melting points.Figure optionsDownload as PowerPoint slide