La(NH-2,6-i-Pr2C6H3)3(pyridine)2 | 713141-07-2

• 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: La(NH-2,6-i-Pr2C6H3)3(pyridine)2
• CAS: 713141-07-2
• 化学式: C₄₆H₆₄LaN₅
• 分子量: 825.953
• InChiKey: FHWUMFXWTVRDFE-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：

  吡啶 、 La2(μ-NH-2,6-i-Pr2C6H3)2(NH-2,6-i-Pr2C6H3)4 以 甲苯 为溶剂， 以75%的产率得到La(NH-2,6-i-Pr2C6H3)3(pyridine)2
  参考文献：
  名称：

  A Comparative Study of π-Arene-Bridged Lanthanum Arylamide and Aryloxide Dimers. Solution Behavior, Exchange Mechanisms, and X-ray Crystal Structures of La₂(NH-2,6-ⁱPr₂C₆H₃)_6, La(NH-2,6-ⁱPr₂C₆H₃)₃(THF)₃, and La(NH-2,6-ⁱPr₂C₆H₃)₃(py)₂

  摘要：

  Reaction of 3 equiv of 2,6-diisopropylaniline with La[N(SiMe3)(2)](3) produces the dimeric species La-2(NHAr)(6) (1). X-ray crystallography reveals a centrosymmetric structure, where the dimeric unit is bridged by intermolecular eta(6)-arene interactions of a unique arylamide ligand attached to an adjacent metal center. Exposure of 1 to THF results in formation of the monomeric tris-THF adduct La(NHAr)3(THF)3 (2), which was shown by X-ray crystallography to maintain a fac-octahedral structure in the solid state. H-1 NMR spectroscopy illustrates that the binding of THF to 1 to form 2 is reversible and removal of THF under vacuum regenerates dimeric 1. Addition of pyridine to 1 yields the monomeric bis-pyridine adduct La(NHAr)(3)(py)(2) (3), which exhibits a distorted trigonal-bipyramidal La metal center. Solution H-1 NMR, IR, and Raman spectroscopy indicate that the pi-arene-bridged dimeric structure of 1 is maintained in solution. Variable-temperature H-1 NMR spectroscopic investigations of 1 are consistent with a monomer-dimer equilibrium at elevated temperature. In contrast, variable-temperature H-1 NMR spectroscopic investigations of the aryloxide analogue La-2(OAr)(6) (4) show that the bridging and terminal aryloxide groups exchange by a mechanism in which the dimeric nature of the compound is retained. Density functional theory (DFT) calculations were carried out on model compounds La-2(OC6H5)(6), La-2(NHC6H5)(6), and (C6H5R)La(XC6H5)(3), where X = O or NH and R = H, OH, or NH2. The formation of eta(6)-arene interactions is energetically favored over monomeric LaX3 (X = OPh or NHPh) with the aryloxide pi-arene interaction being stronger than the arylamide T-arene interaction. Calculation of vibrational frequencies reveals the origin of the observed IR spectral behavior of both La-2(OC6H5)(6) and La-2(NHC6H5)(6), with the higher energy nu(C=C) stretch due to terminal ligands and the lower energy stretch associated with the bridging ligands.

  DOI：

  10.1021/ja0398262