[(triphenylphosphine)3Rh(trifluoromethyl)] | 1139817-73-4

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: [(triphenylphosphine)3Rh(trifluoromethyl)]
• 英文别名: [(Ph3P)3Rh(CF3)]
• CAS: 1139817-73-4
• 化学式: C₅₅H₄₅F₃P₃Rh
• 分子量: 958.784
• InChiKey: ADJNJKYWJQOTRM-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  None
• 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：

  trans-[(triphenylphosphine)2Rh(CF2)F] 、 三苯基膦 以 氘代四氢呋喃 为溶剂， 生成 [(triphenylphosphine)3Rh(trifluoromethyl)]
  参考文献：
  名称：

  Fluxionality of [(Ph₃P)₃M(X)] (M = Rh, Ir). The Red and Orange Forms of [(Ph₃P)₃Ir(Cl)]. Which Phosphine Dissociates Faster from Wilkinson’s Catalyst?

  摘要：

  NMR studies of intramolecular exchange in [(Ph3P)(3)Rh(X)] (X = CF3, CH3, H, Ph, Cl) have produced full sets of activation parameters for X = CH3 (E-a = 16.4 +/- 0.6 kcal mol(-1), Delta H-double dagger= 16.0 +/- 0.6 kcal mol(-1), and Delta S-double dagger = 12.7 +/- 2.5 eu), H (E-a = 10.7 +/- 0.2 kcal mol(-1), Delta H-double dagger = 10.3 +/- 0.2 kcal mol(-1), and Delta S double dagger = -7.2 +/- 0.8 eu), and Cl (E-a = 16.3 +/- 0.2 kcal mo1(-1), Delta H double dagger = 15.7 +/- 0.2 kcal mol(-1), and Delta S double dagger = 0.8 +/- 0.8 eu). Computational studies have shown that for strong trans influence ligands (X = H, Me, Ph, CF3), the rearrangement occurs via a near-trigonal transition state that is made more accessible by bulkier ligands and strongly donating X. The exceedingly fast exchange in novel [(Ph3P)(3)Rh(CF3)] (12.1 s(-1) at -100 degrees C) is due to strong electron donation from the CF3 ligand to Rh, as demonstrated by computed charge distributions. For weaker donors X, this transition state is insufficiently stabilized, and hence intramolecular exchange in [(Ph3P)(3)Rh(Cl)] proceeds via a different, spin-crossover mechanism involving triplet, distorted-tetrahedral [(Ph3P)(3)Rh(Cl)] as an intermediate. Simultaneous intermolecular exchange of [(Ph3P)(3)Rh(Cl)] with free PPh3 (THF) via a dissociative mechanism occurs exclusively from the sites cis to Cl (E-a = 19.0 +/- 0.3 kcal mol(-1), Delta H double dagger = 18.5 +/- 0.3 kcal mol(-1), and Delta S double dagger = 4.4 +/- 0.9 eu). Similar exchange processes are much slower for [(Ph3P)(3)Ir(Cl)] which has been found to exist in orange and red crystallographic forms isostructural with those of [(Ph3P)(3)Rh(Cl)].

  DOI：

  10.1021/ja1039693

文献信息

• Fluxionality of [(Ph₃P)₃Rh(X)]: The Extreme Case of X = CF₃
  作者：Jenni Goodman、Vladimir V. Grushin、Roman B. Larichev、Stuart A. Macgregor、William J. Marshall、D. Christopher Roe

  DOI：10.1021/ja9005699

  日期：2009.4.1

  degrees C), DeltaH(double dagger) = 16.0 +/- 0.6 kcal mol(-1), and DeltaS(double dagger) = 12.8 +/- 2.3 e.u. Intramolecular exchange in [(R(3)P)(3)Rh(X)] occurs (DFT, MP2//BP86) via a distorted trigonal transition state (TS) with X in an axial position trans to a vacant site. The rearrangement is governed by a combination of steric and electronic factors and is facilitated by bulkier ligands on Rh as

  [(Ph(3)P)(3)Rh(F)] 与 CF(3)SiMe(3) 反应生成反式-[(Ph(3)P)(2)Rh(CF(2))(F )] (1; X 射线)，它与溶液中的多种物质平衡。添加过量的 Ph(3)P 将所有平衡移至 [(Ph(3)P)(3)Rh(CF(3))] (2; X-ray) 作为唯一的 NMR 可观察和分离的 (84 ％） 物种。复合物 2 在溶液中具有独特的高度流动性，即使在 -100 摄氏度（12.1 s(-1)）下也能保持配体交换。已确定活化参数（变温 (31)P NMR）在 Me 类似物 2 中类似但较慢的交换，[(Ph(3)P)(3)Rh(CH(3))]：E( a) = 16.5 +/- 0.6 kcal mol(-1), DeltaG(double dagger) = 12.9 kcal mol(-1)（在 -30 摄氏度计算），DeltaH（双匕首）= 16.0