High temperature ethylene polymerization catalyzed by titanium(<scp>iv</scp>) complexes with tetradentate aminophenolate ligands in cis-O, N, N chelating mode
作者:Ruiguo Zhao、Taotao Liu、Liying Wang、Haiyan Ma
DOI:10.1039/c4dt01122h
日期:——
tetradentate aminophenolate ligands were synthesized from the direct reaction of TiCl4(THF)2 with 1 equiv. of the corresponding aminophenol in the presence of triethylamine. For comparison purposes, titanium isopropoxide complexes 5e–8e were also synthesized via the reaction of Ti(OiPr)4 and 1 equiv. of the proligand. Similar reactions of ZrCl4(THF)2 with the corresponding aminophenol ligands in the presence
由TiCl 4(THF)2与1当量的直接反应合成了一系列与爪型四齿氨基酚盐配体连接的三氯化钛配合物1a-4a,7a-10a。在三乙胺存在下制备相应的氨基苯酚。为了进行比较,还通过Ti(O i Pr)4和1当量的反应合成了异丙醇钛络合物5e-8e。配体的。ZrCl 4(THF)2与相应的氨基苯酚配体在三乙胺存在下的类似反应仅允许分离锆配合物8b。X射线衍射研究表明,三氯化钛配合物2a,9a和三异丙氧基钛配合物5e均具有扭曲的八面体几何形状,四齿氨基酚酸酯配体处于顺式-O,N,N螯合模式,其中芳基单元的甲氧基确实存在在固态时不与金属中心协调。经MMAO活化后,这些钛和锆(IV)配合物在30–120°C的温度下对乙烯聚合表现出中等至高的催化活性,从而生产出分布广泛的高分子量聚乙烯(M w / M n= 10.2–34.8)。在高温下,三氯化钛配合物的活性明显高于异丙醇钛和三氯化锆配合物的活性。通