structures of complexes 2, 8, and 11 were established by single-crystal X-ray diffraction studies. Upon activation with methylaluminoxane, complexes 1–9 are active for ethylene polymerization. The activities and half-lifes of the catalyst systems based on zirconium complexes are more than 106 g of polyethylene (mol Zr)−1 h–1 and 6 h, respectively. Complex 9 is more active and long-lived, with a turnover frequency
一系列三齿双阴离子
配体[4- t Bu-6-R-2-(3-R'-5- t Bu-2-OC 6 H 2)N = CH C 6 H 2 O] 2–(L) [R = R'= t Bu(L1); R = CMe 2 Ph,R'= t Bu(
L2); R =
金刚烷基,R'= t Bu(L3);R = R'= CMe 2 Ph(L4); 合成R = SiMe 2 t Bu,R′= CMe 2 Ph(L5)]。TiCl 4与1当量
配体的反应
甲苯中的L1 - L5可得到通式LTiCl 2 [L = L1(1);的五配位
钛络合物。
L2(2); L3(3); L4(4); L5(5)]。向
钛络合物5中添加
四氢呋喃(THF)容易得到THF溶剂化的六配位络合物6,其也通过使TiCl 4与1当量的
配体L5在THF中反应而获得。ZrCl 4与1或2当量的
配体L1 - L5的反应得到六配位
锆单(
配体)
锆配合物LZrCl