[η1:η3-tert-butyl(dimethylfluorenylsilyl)amido]dimethyl hafnium | 154789-28-3

• 英文名称: [η1:η3-tert-butyl(dimethylfluorenylsilyl)amido]dimethyl hafnium
• CAS: 154789-28-3
• 化学式: C₂₁H₂₉HfNSi
• 分子量: 502.043
• InChiKey: CRSAONWCDBIYDG-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
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• 重原子数：
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• 可旋转键数：
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• 环数：
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• sp3杂化的碳原子比例：
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• 拓扑面积：
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• 氢给体数：
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• 氢受体数：
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反应信息

• 作为产物：
  描述：

  甲基溴化镁 、 氯化铪 、 [η1:η3-tert-butyl(dimethylfluorenylsilyl)amido]dimethyl titanium 在 MeLi 作用下， 以 乙醚 、 正己烷 、 正戊烷 为溶剂， 以42.2%的产率得到[η1:η3-tert-butyl(dimethylfluorenylsilyl)amido]dimethyl hafnium
  参考文献：
  名称：

  Stereospecific polymerization of propylene with group 4 ansa-fluorenylamidodimethyl complexes

  摘要：

  Group 4 [eta(1):eta(3)-tert-butyl(dimethylfluorenylsilyl)amido]dimethyl complexes [t-BuNSiMe(2)Flu]MMe2 (M = Ti, 1; Zr, 2; Hf, 3) were synthesized in a one-pot synthesis starting from the ligand, MeLi and MCl4 (M = Ti, Zr, Hf), respectively. The structures of these complexes were determined by X-ray crystallography and the results obtained revealed that the fluorenyl ligand coordinates to center metal in a eta(3)-manner irrespective of center metal employed. Propylene polymerization was conducted at 0 or 20 degrees C in toluene by 1-3 combined with dried methylaluminoxane (MAO), which was prepared from the toluene solutions of MAO by removing free trialkylaluminiums, and HNMe2PhB(C6F5)(4) in the presence of triisobutylaluminium. The 1-dried MAO system gave the polymer with syndiotactic triad (rr) of 63% at 0 degrees C, whereas 2 and 3 did not give any polymer in the same conditions. The 2-dried MAO system gave the polymer with the highest syndiotacticity (rr = 97%) at 20 degrees C, although the activity was low. The 3-dried MAO system did not give any polymer even at 20 degrees C. When HNMe2PhB(C6F5)(4) was used in place of dried MAO at 20 degrees C, 1 gave almost atactic polymer, while 2 and 3 gave highly syndiotactic one (rr > 90%). These results indicate that the catalytic performance strongly depended on the center metal of the ansa-fluorenylamidodimethyl complexes as well as cocatalysts employed. (c) 2005 Elsevier B. V. All rights reserved.

  DOI：

  10.1016/j.jorganchem.2005.08.027