The synthesis, structure and ethene polymerisation catalysis of mono(salicylaldiminato) titanium and zirconium complexes
作者:Dale A. Pennington、William Clegg、Simon J. Coles、Ross W. Harrington、Michael B. Hursthouse、David L. Hughes、Mark E. Light、Mark Schormann、Manfred Bochmann、Simon J. Lancaster
DOI:10.1039/b414229b
日期:——
The silyl ethers 3-But-2-(OSiMe3)C6H3CHNR (2a–e) have been prepared by deprotonation of the known iminophenols (1a–e) and treatment with SiClMe3
(a, R = C6H5; b, R = 2,6-Pri2C6H3; c, R = 2,4,6-Me3C6H2; d, R = 2-C6H5C6H4; e, R = C6F5). 2a–c react with TiCl4 in hydrocarbon solvents to give the binuclear complexes [Ti3-But-2-(O)C6H3CHN(R)}Cl(µ-Cl3)TiCl3]
(3a–c). The pentafluorophenyl species 2e reacts with TiCl4 to give the known complex Ti3-But-2-(O)C6H3CHN(R)}2Cl2. The mononuclear five-coordinate complex, Ti3-But-2-(O)C6H3CHN(2,4,6-Me3C6H2)}Cl3
(4c), was isolated after repeated recrystallisation of 3c. Performing the dehalosilylation reaction in the presence of tetrahydrofuran yields the octahedral, mononuclear complexes Ti3-But-2-(O)C6H3CHN(R)}Cl3(THF)
(5a–e). The reaction with ZrCl4(THF)2 proceeds similarly to give complexes Zr3-But-2-(O)C6H3CHN(R)}Cl3(THF)
(6b–e). The crystal structures of 3b, 4c, 5a, 5c, 5e, 6b, 6d, 6e and the salicylaldehyde titanium complex Ti3-But-2-(O)C6H3CHO}Cl3(THF)
(7) have been determined. Activation of complexes 5a–e and 6b–e with MAO in an ethene saturated toluene solution gives polyethylene with at best high activity depending on the imine substituent.
硅醚3-But-2-(OSiMe3)C6H3CHNR(2a-e)通过已知的亚胺酚(1a-e)去质子化并与SiClMe3处理制备而成(a,R=C6H5;b,R=2,6-Pri2C6H3;c,R=2,4,6-Me3C6H2;d,R=2-C6H5C6H4;e,R=C6F5)。2a-c与TiCl4在烃溶剂中反应生成双核配合物[Ti3-But-2-(O)C6H3CHN(R)}Cl(µ-Cl3)TiCl3](3a-c)。五氟苯基物种2e与TiCl4反应生成已知配合物Ti3-But-2-(O)C6H3CHN(R)}2Cl2。通过反复重结晶3c,分离出单核五配位配合物Ti3-But-2-(O)C6H3CHN(2,4,6-Me3C6H2)}Cl3(4c)。在四氢呋喃的存在下进行去卤硅化反应,得到八面体、单核配合物Ti3-But-2-(O)C6H3CHN(R)}Cl3(THF)(5a-e)。与ZrCl4(THF)2的反应类似,生成配合物Zr3-But-2-(O)C6H3CHN(R)}Cl3(THF)(6b-e)。已确定3b、4c、5a、5c、5e、6b、6d、6e以及水杨醛钛配合物Ti3-But-2-(O)C6H3CHO}Cl3(THF)(7)的晶体结构。用MAO在乙烯饱和的甲苯溶液中激活5a-e和6b-e配合物可生成聚乙烯,其活性高低取决于亚胺取代基。