Oxide-Bridged Heterobimetallic Aluminum/Zirconium Catalysts for Ethylene Polymerization
Oxide-Bridged Heterobimetallic Aluminum/Zirconium Catalysts for Ethylene Polymerization
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DOI：
10.1002/ejic.201500123
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发表时间：
2015-04-01
影响因子：
2.3
通讯作者：
Harder, Sjoerd
中科院分区：
文献类型：
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作者：
Boulho, Cedric;Zijlstra, Harmen S.;Harder, Sjoerd
双金属铝/锆配合物Cp*Zr-2(Me) al (DIPH) [DIPH- h -2 = 3,3-二（2-甲基烯丙基）-（1,1-联苯基）-2,2-二醇]；以（DIPH）AlMe和Cp*Zr-2(Me)OH为原料，制备了Cp* = C5Me5]。与Roesky的催化剂Cp2Zr(Me)O(Me)Al(DIPP-nacnac) {DIPP-nacnac = CH[(CMe)(2,6- ipr (2)C(6)H(3)N)](2)}相比，它不含Al-Me官能团，并且在Al上具有更高的Lewis酸度。铝配合物（DIPH）AlMe和双金属Al/Zr的晶体结构和核磁共振光谱显示在这两种情况下都是二聚物。[Cp*Zr-2(Me)OAl(DIPH)](2)的晶体结构为平面Al2O2核心和端部Cp*Zr-2(Me)O基团。研究了含多种清除剂的双金属配合物在甲苯中的乙烯聚合反应。在相同的聚合条件下，甲基铝氧烷活化产物的活性与Cp*2ZrCl2和Roesky双金属配合物Cp2Zr(Me)OAl(Me)（DIPP-nacnac）相似，具有相对较窄的多分散性指数（2.47）。
A bimetallic aluminum/zirconium complex Cp*Zr-2(Me)OAl(DIPH) [DIPH-H-2 = 3,3-bis(2-methylallyl)-(1,1-biphenyl)-2,2-diol; Cp* = C5Me5] was prepared in good yield by the reaction of (DIPH)AlMe with Cp*Zr-2(Me)OH. In contrast to Roesky's catalyst, Cp2Zr(Me)O(Me)Al(DIPP-nacnac) {DIPP-nacnac = CH[(CMe)(2,6-iPr(2)C(6)H(3)N)](2)}, it contains no Al-Me functionality and has increased Lewis acidity at Al. Crystal structures and the NMR spectra of the aluminum complex (DIPH)AlMe and the bimetallic Al/Zr species reveal in both cases dimeric complexes. The crystal structure of [Cp*Zr-2(Me)OAl(DIPH)](2) shows a planar Al2O2 core and a terminal Cp*Zr-2(Me)O group. Ethylene polymerization in toluene was studied for the bimetallic complex with a variety of scavengers. Under comparable polymerization conditions, the methylalumoxane-activated species show high activities that are similar to those obtained with Cp*2ZrCl2 and Roesky's bimetallic complex Cp2Zr(Me)OAl(Me)(DIPP-nacnac), with a relatively narrow polydispersity index (2.47).