(tributylphosphine)(cyclopentadienyl)(2,4-dimethylpentadienyl)titanium | 172221-04-4

• 英文名称: (tributylphosphine)(cyclopentadienyl)(2,4-dimethylpentadienyl)titanium
• CAS: 172221-04-4
• 化学式: C₂₄H₄₃PTi
• 分子量: 410.459
• InChiKey: GENXTUZPAYUMMC-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：

  2,4-dimethylpentadienyl potassium 、 、 三丁基膦 以 四氢呋喃 为溶剂， 生成 (tributylphosphine)(cyclopentadienyl)(2,4-dimethylpentadienyl)titanium
  参考文献：
  名称：

  Pentadienyl as a Stronger Binding but More Reactive Ligand Than Cyclopentadienyl: Syntheses, Reactions, and Molecular Orbital Studies of Half-Open Titanocenes

  摘要：

  The reactions of Ti(C5H5)Cl-2(PR(3)) complexes (R = Me, Et) with 2 equiv of a potassium pentadienide such as KC5H7 or K(2,4-C7H11) (C7H11 = dimethylpentadienyl) lead to the formation of diamagnetic 16 electron half-open titanocenes as monophosphine adducts. A single-crystal X-ray diffraction study of Ti(C5H5)(2,4-C7H11)(PEt(3)) revealed that the Ti-C bond lengths for the open dienyl ligand were much shorter than those for the C5H5 ligand, 2.240(3) vs 2.346(4) Angstrom, indicative of stronger Ti-C7H11 bonding. Reaction of this complex with CH3CN leads to loss of the PEt(3) ligand and coupling to the 2,4-C7H11 ligand. Thus, the C7H11 ligand is not only more strongly bound than C5H5, it is also more reactive. A structural determination of this complex confirmed the mode of coupling and revealed that a dimeric species was formed. The phosphine ligands in the various complexes may readily be replaced by P(OMe)(3) or P(OEt)(3). The Ti(C5H5)(2,4-C7H11)(PEt(3)) complex also reacts with CO, leading to a thermally unstable monocarbonyl and a thermally unstable dicarbonyl. While spectroscopic data revealed a symmetric structure for the monocarbonyl, the dicarbonyl complex is clearly unsymmetric. Molecular orbital calculations provide confirmation of stronger titanium-pentadienyl bonding and also the fact that the pentadienyl ligands serve as much better electron accepters than cyclopentadienyl. To a large extent these may both be attributed to significant delta bonding interactions between titanium d(xy) and pentadienyl pi(4)* orbitals.

  DOI：

  10.1021/om00011a023