[Zr(η5-C5H5)(η5-C5H(CH3)4)Cl2] | 169904-66-9

• 分子结构分类: 有机化合物 - 碳氢化合物 - 芳香烃
• 英文名称: [Zr(η5-C5H5)(η5-C5H(CH3)4)Cl2]
• 英文别名: cyclopenta-1,3-diene;dichlorozirconium(2+);1,2,3,5-tetramethylcyclopenta-1,3-diene
• CAS: 169904-66-9
• 化学式: C₁₄H₁₈Cl₂Zr
• 分子量: 348.427
• InChiKey: GUAKKDLCHFILLW-UHFFFAOYSA-L

计算性质

• 辛醇/水分配系数(LogP)：
  5.42
• 重原子数：
  17
• 可旋转键数：
  0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.29
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  四甲基环戊二烯锂 、 (二甲氧基乙烷)环戊二烯基锆(IV)氯化物 以 甲苯 为溶剂， 以46%的产率得到[Zr(η5-C5H5)(η5-C5H(CH3)4)Cl2]
  参考文献：
  名称：

  The influence of electronic and steric effects and the importance of polymerization conditions in the ethylene polymerization with zirconocene/MAO catalysts

  摘要：

  A series of Cp'(C5H5)ZrCl2 and Cp' = ZrCl2 precatalysts (Cp' = C(5)Me(4)H, C(4)Me(4)P, C(5)Me(5)) together with (C5H5)(2)ZrCl2 has been investigated in terms of steric and electronic variations and their catalytic activities in combination with methylalumoxane (MAO) towards the polymerization of ethylene are compared. The changes in the steric environment were evaluated on the basis of the structural data available and supplemented by theoretical structural studies on the semiempirical (ZINDO, EHMO) and density functional (DF) level. The X-ray structures of (C(5)Me(4)H)(2)ZrCl2 (3) and (C(4)Me(4)P)(C5H5)ZrCl2 (4) have been determined (3: orthorhombic, Cmcm, a = 6.714(4), b = 17.275(4), c = 15.643(5) Angstrom, Z = 4; 4: monoclinic, P2(1)/c, a = 8.8791(5), b = 7.8051(8), c = 20.9215(10) Angstrom beta = 94.422(4)degrees, Z = 4. Zr-91 NMR data for the above series has been measured and is correlated to changes in the HOMO-LUMO gap available from electronic structure calculations. Under mostly homogeneous polymerization conditions, at very low zirconium concentrations the order of the catalytic activity found for ethylene polymerizations is (C5H5)(2)ZrCl2 > (C(5)Me(4)H)(C5H5)ZrCl2 > (C(5)Me(5))(C5H5)ZrCl2 > (C(4)Me(4)P)(C5H5)ZrCl2 > (C(5)Me(4)H)(2)ZrCl2 > > (C(5)Me(4))(2)ZrCl2 > (C(4)Me(4)P)(2)ZrCl2, which for the most part is inversely proportional to the steric demand of the ring ligands in the metallocene precatalysts except for the phospholyl systems. The lower activities of the phospholyl vs. the tetra- and penta-methylcyclopentadienyl compounds might imply an electronic effect such that the electron withdrawing phosphorus substituent decreases the activity, although further studies are needed to clarify this situation. Emphasis is placed on the control of the polymerization conditions and evaluation of the time-activity profiles. At higher zirconium concentrations an increased precipitation of polyethylene takes place during the course of polymerization and results in a transfer to the heterogeneous phase with a diffusion controlled reaction rate thereby invalidating any activity-comparing studies.

  DOI：

  10.1016/0022-328x(95)05647-8

文献信息

• Synthesis of racemic chiral-at-metal complexes of the Group 4 metals
  作者：Nathaniel W Alcock、Howard J Clase、David J Duncalf、Suzanne L Hart、Andrew McCamley、Peter J McCormack、Paul C Taylor

  DOI：10.1016/s0022-328x(00)00253-9

  日期：2000.6

  ched products can not be isolated due to formation of complexes between the Group 4 metallocene products and the borane by-products. An efficient method for synthesis of racemic chiral-at-metal metallocenes, through lithium chloride catalysed ligand redistribution reactions, is described. Sterically-hindered racemic chiral-at-metal complexes are prepared by nucleophilic substitution of prochiral dichlorides

  描述了用于手性金属配合物的不对称合成的方案，但是由于第4族茂金属产物和硼烷副产物之间形成配合物，因此不能分离出对映体富集的产物。描述了一种通过氯化锂催化的配体再分布反应合成外消旋手性金属茂金属的有效方法。通过亲核取代前手性二氯化物制备立体受阻的外消旋手性金属配合物。