| 192436-27-4

• CAS: 192436-27-4
• 化学式: C₂F₃O₂*C₂₃H₃₉NNbSi₂
• 分子量: 591.663
• InChiKey: DLTTWEVPSDELMS-UHFFFAOYSA-M

计算性质

• 辛醇/水分配系数(LogP)：
  None
• 重原子数：
  None
• 可旋转键数：
  None
• 环数：
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• sp3杂化的碳原子比例：
  None
• 拓扑面积：
  None
• 氢给体数：
  None
• 氢受体数：
  None

反应信息

• 作为产物：
  描述：

  [Nb(η5-C5H4SiMe3)2(H)(cyclohexylisocyanido)] 、 三氟乙酸 以 氘代丙酮 为溶剂， 生成
  参考文献：
  名称：

  Synthesis and Spectroscopic Properties of Dihydrogen Isocyanide Niobocene [Nb(η⁵-C₅H₄SiMe₃)₂(η²-H₂)(CNR)]⁺ Complexes. Experimental and Theoretical Study of the Blocked Rotation of a Coordinated Dihydrogen

  摘要：

  Synthesis of stable hydride isocyanide derivatives Nb(eta(5)-C5H4SiMe3)(2)(H)(CNR) has been achieved through the formation of coordinatively unsaturated 16-electron species Nb(eta(5)-C5H4SiMe3)(2)H by thermolytic loss of H-2 followed by the coordination of an isocyanide ligand. Low-temperature protonation with a slight excess of CF3COOH leads to the eta(2)-dihydrogen complexes [Nb(eta(5)-C5H4SiMe3)(2)(eta(2)-H-2)(CNR)](+). NMR spectra of these H-H complexes and their monodeuterated H-D isotopomers present a single high-field resonance at room temperature. By lowering the temperature to 178 K, decoalescence of the signal was observed for the H-D complexes but not for the H-H ones. By combining DFT electronic structure calculations with a monodimensional rotational tunneling model, it has been shown that the absence of decoalescence of the H-H signal is due to the existence of a very large exchange coupling. Conversely, for the H-D isotopomer, the difference in zero point energy corresponding to two nonequivalent (H-D and D-H) positions leads to a slight asymmetry which dramatically reduces the exchange coupling, allowing decoalescence to be observed. Therefore, the H-D classical rotation and the quantum exchange processes will not be practically observed for this complex, whereas only the classical process for the H-H species is quenched out on the NMR time scale.

  DOI：

  10.1021/ja9640354