germacyclopentane | 3466-01-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 金属杂环化合物
• 英文名称: germacyclopentane
• 英文别名: Germano-cyclopentan；Germanocyclopentan；Germacyclopentan；Silacyclopentan；germolane
• CAS: 3466-01-1
• 化学式: C₄H₁₀Ge
• 分子量: 130.713
• InChiKey: WJECKLIHWFGVPU-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.79
• 重原子数：
  5
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为产物：
  描述：

  1,4-二溴丁烷 、 四氯化锗 在 magnesium 作用下， 以 乙醚 为溶剂， 生成 germacyclopentane
  参考文献：
  名称：

  Conformational stability, r0 structural parameters, ab initio calculations, and vibrational assignment for germacyclopentane

  摘要：

  The infrared spectra (3500-50 cm(-1)) of the gas and solid and the Raman spectrum (3200-30 cm(-1)) of liquid germacyclopentane, c-C4H8GeH2, have been recorded. Additionally, the infrared spectra (3200-400 cm(-1)) of liquid xenon solutions have been recorded at -65 and -95 degrees C. In all of the physical states only the twisted C-2 conformer was detected. The conformational energetics have been calculated with the Moller-Plesset perturbation method to the second order, (MP2(full)) as well as with density functional theory by the B3LYP method utilizing a variety of basis sets up to 6-311G(2d,2p). All of these calculations predict only the twisted conformer as the stable form with an average barrier to planarity of 2756 cm-1 (32.97 kJ/mol) from the MP2 calculations and a significantly lower value of 2128 cm-1 (25.45 kJ/mol) from the DFT calculations with neither calculations being significantly effect by inclusion of diffuse functions. The C-s conformer (envelope) has a lower energy of 700 cm(-1) (MP2) and 400 cm(-1) (B3LYP) than the planar form. Thus, the path between the two identical C-2 conformers is by a pseudorotational motion rather than through the planar form. From the isolated GeH frequency from the GeHD isotopomer the GeH distance was calculated to be 1.532(2) A. By utilizing the previously reported microwave rotational constants for four isotopomers (Ge-70, Ge-72, Ge-73, Ge-74) combined with the structural parameters predicted from the MP2(full)/6-311+G(d,p) calculations, adjusted r(0) structural parameters were obtained. The determined heavy atom distances are: r(0)(GeC) = 1.972(5); r(0)(C2C4) and (C3C5) = 1.541(5); and r(0)(C4C5) = 1.533(5) A and the angles in degrees: angle CGeC = 93.6(5)degrees; angle GeCC = 102.6(5)degrees; angle CCC = 109.4(5)degrees with the two dihedral angles angle GeCCC = -38.4(3)degrees and angle CCCC = 53.7(3)degrees. A complete vibrational assignment is given for the twisted (C2) conformer for the normal species and the GeD2 isotopomer which are supported by normal coordinate calculations with scaled force constants from MP2(full)/6-31G(d) calculations. The results of these spectroscopic and theoretical studies are discussed and compared to the corresponding results for some similar molecules. (C) 2006 Elsevier B.V. All rights reserved.

  DOI：

  10.1016/j.molstruc.2006.11.050

文献信息

• NMR Spectra of Organogermanium Compounds. X. Syntheses,¹³C and⁷³Ge NMR Spectra and Molecular Mechanics Calculations of Germacyclopentanes and Germacyclopentenes
  作者：Yoshito Takeuchi、Katsumi Tanaka、Toshie Harazono

  DOI：10.1246/bcsj.64.91

  日期：1991.1

  Germacyclopentane, its 1-methyl, and 1,1-dimethyl derivatives together with some germacyclopentenes were prepared and their 13C and 73Ge NMR spectra were determined. Molecular mechanics calculations of germacyclopentanes indicate that the symmetric twist form is the most stable in contrast to cyclopentane where the envelop and twist forms have much the same energy. Though both 13C and 73Ge chemical shifts are less sensitive to the stereochemistry of the methyl group as compared with the corresponding germacyclohexanes, the spectroscopic results can be explained in terms of the structures as depicted by molecular mechanics calculations.

  合取环戊烷及其1-甲基和1,1-二甲基衍生物，以及一些合取环戊烯被合成，并测定了它们的13C和73Ge NMR谱。合取环戊烷的分子力学计算表明，在对比环戊烷时，对称扭曲形式是最稳定的，而环戊烷的包层和扭曲形式能量相差不大。尽管与对应的合取环己烷相比，13C和73Ge化学位移对甲基立体化学的敏感性较低，但光谱结果可以通过分子力学计算所描绘的结构进行解释。
• Conformational stability, r0 structural parameters, ab initio calculations, and vibrational assignment for germacyclopentane
  作者：Gamil A. Guirgis、Ahmed M. El Defrawy、Todor K. Gounev、Mamdouh S. Soliman、James R. Durig

  DOI：10.1016/j.molstruc.2006.11.050

  日期：2007.5

  The infrared spectra (3500-50 cm(-1)) of the gas and solid and the Raman spectrum (3200-30 cm(-1)) of liquid germacyclopentane, c-C4H8GeH2, have been recorded. Additionally, the infrared spectra (3200-400 cm(-1)) of liquid xenon solutions have been recorded at -65 and -95 degrees C. In all of the physical states only the twisted C-2 conformer was detected. The conformational energetics have been calculated with the Moller-Plesset perturbation method to the second order, (MP2(full)) as well as with density functional theory by the B3LYP method utilizing a variety of basis sets up to 6-311G(2d,2p). All of these calculations predict only the twisted conformer as the stable form with an average barrier to planarity of 2756 cm-1 (32.97 kJ/mol) from the MP2 calculations and a significantly lower value of 2128 cm-1 (25.45 kJ/mol) from the DFT calculations with neither calculations being significantly effect by inclusion of diffuse functions. The C-s conformer (envelope) has a lower energy of 700 cm(-1) (MP2) and 400 cm(-1) (B3LYP) than the planar form. Thus, the path between the two identical C-2 conformers is by a pseudorotational motion rather than through the planar form. From the isolated GeH frequency from the GeHD isotopomer the GeH distance was calculated to be 1.532(2) A. By utilizing the previously reported microwave rotational constants for four isotopomers (Ge-70, Ge-72, Ge-73, Ge-74) combined with the structural parameters predicted from the MP2(full)/6-311+G(d,p) calculations, adjusted r(0) structural parameters were obtained. The determined heavy atom distances are: r(0)(GeC) = 1.972(5); r(0)(C2C4) and (C3C5) = 1.541(5); and r(0)(C4C5) = 1.533(5) A and the angles in degrees: angle CGeC = 93.6(5)degrees; angle GeCC = 102.6(5)degrees; angle CCC = 109.4(5)degrees with the two dihedral angles angle GeCCC = -38.4(3)degrees and angle CCCC = 53.7(3)degrees. A complete vibrational assignment is given for the twisted (C2) conformer for the normal species and the GeD2 isotopomer which are supported by normal coordinate calculations with scaled force constants from MP2(full)/6-31G(d) calculations. The results of these spectroscopic and theoretical studies are discussed and compared to the corresponding results for some similar molecules. (C) 2006 Elsevier B.V. All rights reserved.