State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
Dalton Trans. 2014 Jan 7;43(1):222-30. doi: 10.1039/c3dt51659h.
A series of novel half-zirconocenes containing phosphine-(thio)phenolate chelating ligands of the type Cp'Zr(thf)Cl2[X-2-R(1)-4-R(2)-6-(PPh2)C6H2] (Cp' = C5Me5, 2a: X = O, R(1) = Ph, R(2) = H; 2b: X = O, R(1) = (t)Bu, R(2) = H; 2c: X = O, R(1) = R(2) = (t)Bu; 2d: X = O, R(1) = SiMe3, R(2) = H; 2e: X = S, R(1) = SiMe3, R(2) = H; Cp' = C5H5, 3b: X = O, R(1) = (t)Bu, R(2) = H; 3c: X = O, R(1) = R(2) = (t)Bu; 3d: X = O, R(1) = SiMe3, R(2) = H; 3e: X = S, R(1) = SiMe3, R(2) = H) have been synthesized in high yields (74-85%). These complexes were identified by (1)H, (13)C and (31)P NMR as well as elemental analyses. Structural analysis for 2a-b and 2d revealed that these complexes adopt six-coordinate, distorted octahedral geometry around the zirconium center. These novel half-zirconocenes possessed high catalytic performance for ethylene polymerization at high temperature in the presence of MMAO. The phosphine-phenolate-based Cp* complexes produced high molecular weight polymers (M(W) > 400,000), while the Cp analogues displayed much higher activities at high temperature. Complex 3c with MMAO showed a maximum ethylene polymerization activity of 17,580 kg mol(Zr)(-1) h(-1) at 75 °C. In addition, the Cp based complexes 3b-e could promote ethylene and 1-hexene copolymerization with high activities.
一系列新型半锆杂环戊二烯基膦（硫）苯并二氢吡喃配合物，配体为 CP'Zr(thf)Cl2[X-2-R(1)-4-R(2)-6-(PPh2)C6H2]，其中 CP'=C5Me5，2a：X=O，R(1)=Ph，R(2)=H；2b：X=O，R(1)=(t)Bu，R(2)=H；2c：X=O，R(1)=R(2)=(t)Bu；2d：X=O，R(1)=SiMe3，R(2)=H；2e：X=S，R(1)=SiMe3，R(2)=H；CP'=C5H5，3b：X=O，R(1)=(t)Bu，R(2)=H；3c：X=O，R(1)=R(2)=(t)Bu；3d：X=O，R(1)=SiMe3，R(2)=H；3e：X=S，R(1)=SiMe3，R(2)=H)以高产率(74-85%)合成。这些配合物通过(1)H、(13)C 和(31)P NMR 以及元素分析来鉴定。2a-b 和 2d 的结构分析表明，这些配合物在锆中心周围采用六配位、扭曲八面体几何形状。这些新型半锆杂环戊二烯基膦(硫)苯并二氢吡喃配合物在 MMAO 的存在下，在高温下对乙烯聚合具有高催化性能。基于膦-苯并二氢吡喃的 CP*配合物产生高分子量聚合物(M(W)>400,000)，而 CP 类似物在高温下显示出更高的活性。与 MMAO 配合的 3c 显示出在 75°C 时的最大乙烯聚合活性为 17580kg mol(Zr)(-1)h(-1)。此外，基于 CP 的配合物 3b-e 可以以高活性促进乙烯和 1-己烯共聚。
