کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1328228 | 977549 | 2007 | 8 صفحه PDF | دانلود رایگان |
A series of titanium complexes bearing a SiMe2-bridged phenoxy-cyclopentadienyl ligand were synthesized and characterized, and their catalytic behavior for copolymerization of ethylene and 1-hexene was investigated. Treatment of dimethylsilyl(2,3,4,5-tetramethylcyclopentadienyl)(3-tert-butyl-5-methyl-2-phenoxy)-titanium dichloride (1) with appropriate nucleophiles afforded dimethoxy complex 2, dimethyl complex 3, and dibenzyl complex 4. Standing a toluene solution of 2 in air afforded a dinuclear μ-oxo complex 5 as a single isomer. 1,3-Diene complexes 6–8 were prepared by reaction of 1 with the corresponding 1,3-dienes in the presence of 2 equiv. of n-BuLi. X-ray analysis of 1,4-diphenyl-1,3-butadiene complex 6 revealed that the diene ligand coordinates to titanium in s-cis fashion with a prone orientation. The newly prepared titanium complexes were applied to copolymerization of ethylene and 1-hexene upon activation with AliBu3 and [C6H5NMe2H][B(C6F5)4]. It was found that the alkyl complexes 3–4 and the diene complexes 6–8 showed higher activities than 1 at elevated temperature.
A series of titanium alkyl, oxo, and diene complexes bearing a SiMe2-bridged phenoxy-cyclopentadienyl ligand were synthesized and characterized, and their catalytic behavior for copolymerization of ethylene and 1-hexene was investigated. X-ray analysis of 1,4-diphenyl-1,3-butadiene complex revealed that the diene ligand coordinates in s-cis fashion to titanium with a prone orientation. Polymerization study revealed that the alkyl complexes and the diene complexes showed higher activities than the starting dichloride at 130 °C.Figure optionsDownload as PowerPoint slide
Journal: Journal of Organometallic Chemistry - Volume 692, Issue 21, 1 October 2007, Pages 4717–4724