dicarbonyl(η(5)-cyclopentadienyl)(2-[tributoxyphosphonio]ethyl)iron tetrafluoroborate | 167413-55-0

• 英文名称: dicarbonyl(η(5)-cyclopentadienyl)(2-[tributoxyphosphonio]ethyl)iron tetrafluoroborate
• CAS: 167413-55-0
• 化学式: BF₄*C₂₁H₃₆FeO₅P
• 分子量: 542.139
• InChiKey: VLLOXLMVTNGYRD-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：

  {CpFe(CO)2(η2-C2H4)}BF4 、 三丁基,三丁酯 以 丙酮 为溶剂， 生成 dicarbonyl(η(5)-cyclopentadienyl)(2-[tributoxyphosphonio]ethyl)iron tetrafluoroborate
  参考文献：
  名称：

  Kinetics and mechanism of addition of tertiary phosphines and phosphites to the dicarbonyl(η⁵-cyclopentadienyl)-(η-ethene)iron cation

  摘要：

  Kinetic studies of the addition of a range of tertiary phosphine and phosphite nucleophiles PR(3) to the cation [Fe(cp)(CO)(2)(eta-C2H4)](+) 1 (cp = eta(5)-C5H5) [equation (i)] revealed the general rate law, Rate = k(1)[Fe][PR(3)]. The second-order rate constants k(1) decrease markedly down the order P(C(6)H(4)OMe-2)(3) > PBu(3)(n) > P(C(6)H(4)OMe-4)(3) > P(C(6)H(4)Me-4)(3) > P(C(6)M(4)Me-4)Ph(2) > PPh(3) > P(C2H4CN-2)Ph(2) > P(C2H4CN-2)(3) > P(C6H4Cl-4)(3) > P(OBu(n))(3). This reactivity order parallels that-of decreasing electron availability at the phosphorus centre, as shown quantitatively by the good correlation between log k(1) and the Tolman Sigma(chi) values. An excellent fit to the Hammett and Bronsted equations is also observed for reaction (i) with the nucleophiles P(C(6)H(4)X-4)(3). The moderate Bronsted slope alpha of[Fe(cp)(CO)(2)(eta-C2H4)](+) + PR(3) --> [Fe(cp)(CO)(2)(C(2)H(4)PR(3))](+) (i)0.46 establishes the importance of phosphine basicity in determining nucleophilicity towards the ethene ligand in cation 1. These results, together with the large negative entropy of activation with PPh(3) (Delta S-1(double dagger) = -103 J K-1 mol(-1)), are interpreted in terms of direct addition (k(1)) of the phosphorus nucleophiles to the ethene ligand in 1 and suggest a transition state in which there is build-up of positive charge on the phosphorus centre and considerable phosphorus-carbon bond formation.

  DOI：

  10.1039/dt9950002021