cyclopentadienyl ligands, (C5H4-t-Bu)2ZrCl2 (2), (C5H3-1,2-t-Bu2)2ZrCl2 (3) and (C5H3-1,3-t-Bu2)2ZrCl2 (4), have been employed as methylaluminoxane (MAO)-activated catalysts for polymerization of 1-hexene under high pressure conditions (100–750 MPa=ca. 1000–7500 atm). Comparison with some non and methyl-substituted metallocenes are also discussed.
一个柄-zirconocene复杂具有邻位二-叔丁基取代的
环戊二烯配位体中,Me 2的Si(C 5 H ^ 4)(C 5 H ^ 2 -3,4-吨-Bu 2)的ZrCl 2(1),已合成并表征了通过X射线衍射(斜方晶系,空间群:PBCA,一个= 18.3690(8),b = 18.0749(12),C ^ = 13.2039(9)埃,V = 4383.9(4)3,ž = 8 ,R = 0.0283,R w= 0.0291)。配合物1由于其空间排斥而具有非常扭曲的结构。然而,在溶液中,即使在-80℃下,两个叔丁基基团在磁性上也是等价的,这表明桥连的
环戊二烯基单元相对于
金属中心的非常快的振荡。配合物1和具有叔丁基取代的
环戊二烯基
配体的未桥接二茂
锆二
氯化物,(C 5 H 4 - t -Bu)2 ZrCl 2(2),(C 5 H 3 -1,2- t -Bu 2)2 ZrCl 2(3)和(C 5 H