(η(5)-BrMe2SiC5H4)(η(5)-C5H5)ZrBr2 | 302342-95-6

• 英文名称: (η(5)-BrMe2SiC5H4)(η(5)-C5H5)ZrBr2
• CAS: 302342-95-6
• 化学式: C₁₂H₁₅Br₃SiZr
• 分子量: 518.273
• InChiKey: ZPBWOTOELLFTFT-UHFFFAOYSA-L

反应信息

• 作为产物：
  描述：

  [Cp(CpSiMe₃)ZrCl₂] 、 三溴化硼 以 1,2-二氯乙烷 为溶剂， 以75%的产率得到(η(5)-BrMe2SiC5H4)(η(5)-C5H5)ZrBr2
  参考文献：
  名称：

  Influence of the Departing Group on the Electrophilic Cleavage of Silicon−Carbon Bonds Adjacent to Zirconocene Dichloride. Preparation of Electrophile-Functionalized Zirconocene Dibromides

  摘要：

  (EtMe2SiC5H4)CpZrCl2 (5) reacts with BBr3 in 1,2-dichloroethane (reflux, 24 h) to afford a 4:1 mixture of (EtMeBrSiC5H4)CpZrBr2 (10) and (BrMe2SiC5H4)CpZrBr2 (11) in a nearly quantitative conversion. Similarly, ((BuMe2SiC5H4)-Bu-t)CpZrCl2 (6) reacts with BBr3 to afford a 15:1 mixture of ((BuMeBrSiC5H4)-Bu-t)CpZrBr2 (13) and 11. The product 11 is obtained independently by treating (Me3SiC5H4)CpZrCl2 (12) with BBr3. In contrast, Si-Ph bonds are cleaved with complete selectivity in the presence of Si-Me groups. (PhMe2SiC5H4)(2)-ZrCl2 (8) reacts with excess BCl3 in dichloromethane (reflux, 15 h) to afford (ClMe2SiC5H4)(2)-ZrCl2 (14) in 72% yield. (Ph2MeSiC5H4)(2)ZrCl2 (9) reacts with excess BBr3 in 1,2-dichloroethane (reflux, 15 h) to afford (Br2MeSiC5H4)(2)ZrBr2 (15) in 79% yield. Complexes 9 and 15 were analyzed by single-crystal X-ray diffraction. Crystalline 9 adopts a pseudo-C-2 conformation in which the face of the Ph group of one ligand shows a weak interaction with a C-H bond of the other ligand. Crystalline 15 also adopts a pseudo-C-2 conformation, in which the SiBr2 groups are directed away from the ZrBr2 group.

  DOI：

  10.1021/om0005452

文献信息

• Ethylene polymerization using silica-supported zirconocene dibromide/methylalumoxane catalysts
  作者：Xu Cheng、Owen W Lofthus、Paul A Deck

  DOI：10.1016/j.molcata.2003.11.022

  日期：2004.4

  Functionalized metallocene precursors (BrMe2SiC5H4)CpZrBr2 (1), (BrMe2SiC5H4)(2)ZrBr2, (2) (Br2MeSiC5H4)(2)ZrBr2 (3), and [1,3-(BrMe2Si)(2)C5H3](2)ZrBr2 (4) were immobilized on partially dehydroxylated silica (PDS) and screened for ethylene polymerization in slurry reactions conducted in toluene using methylalumoxane (MAO) as the cocatalyst. The effects of metallocene precursor structure, catalyst immobilization method, and catalyst loading are presented in terms of catalytic activity, polymer molecular weight distribution, and stability of the catalysts toward leaching. (C) 2003 Elsevier B.V. All rights reserved.