9-<(trimethylsilyl)methyl>fluorene

• 分子结构分类: 有机化合物 - 苯类化合物 - 芴
• 英文名称: 9-<(trimethylsilyl)methyl>fluorene
• 英文别名: 9-((trimethylsilyl)methyl)fluorene；9H-fluoren-9-ylmethyl(trimethyl)silane
• 化学式: C₁₇H₂₀Si
• 分子量: 252.431
• InChiKey: XFOWIGLGHSTSQA-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.14
• 重原子数：
  18
• 可旋转键数：
  2
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.29
• 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：

  9H-芴-9-基锂 、 氯甲基三甲基硅烷 以 四氢呋喃 为溶剂， 生成 9-<(trimethylsilyl)methyl>fluorene
  参考文献：
  名称：

  β-Silyl Effects on the Stabilities of Carbanions and Carbon-Centered Radicals Derived from Ethyl Thionacetates, Diethyl Malonates, and Ethyl Acetoacetates

  摘要：

  The effects of an alpha-Me(3)SiCH(2) group on the equilibrium acidities in DMSO of the acidic C-H bonds in esters, including ethyl thionacetate, diethyl malonate, and ethyl acetoacetate, were found to differ from that of an alpha-MeCH(2) group by less than 1 kcal/mol, pointing to little or no stabilizing effect of a beta-Me(3)Si group on carbanion stabilities. On the other hand, substitution of an alpha-Me(3)SiCH(2) group for one of the acidic hydrogen atoms in these esters to give Me(3)SiCH(2)CH(2)C(=S)OEt, Me(3)SiCH(2)CH(CO(2)Et)(2), and Me(3)SiCH(2)CH(CO(2)Et)COCH3 was found to decrease the homolytic bond dissociation energies (BDEs) of the remaining acidic C-H bonds by 7.1, 8.2, and 7.1 kcal/mol, respectively, relative to those of the parent esters and by 2.7, 4.5, and 4.4 kcal/mol, respectively, relative to the BDEs of the acidic C-H bonds in the corresponding MeCH(2)-substituted esters. The differences in BDEs observed between the Me(3)SiCH(2)- and the MeCH(2)-substituted ester derivatives are indicative of the presence of 3-5 kcal/mol C-H bond stabilizing effects of beta-Me(3)Si groups, relative to those of beta-Me groups, on the corresponding carbon radicals. The BDE value of the acidic C-H bond in Me3(C)CH(2)CH(2)C(=S)OEt was found to be 86.4 kcal/mol, which represents a 0.6 kcal/mol increase in BDE relative to that of the acidic C-H bond in MeCH(2)CH(2)C(=S)OEt. This result demonstrates the absence of a stabilizing effect of a beta-tert-butyl group on an open-chain carbon-centered radical. This is contrary to an apparent 6.4 kcal/mol C-H bond stabilizing effect of the beta-tert-butyl group in 9-neopentylfluorene, relative to that in fluorene, which is attributed to the relief of steric strain in forming the radical.

  DOI：

  10.1021/jo951506g

文献信息

• Effects of .alpha.- and .beta.-Silicon Atoms on the Free Energies of C-H Homolysis and Heterolysis
  作者：M. J. Bausch、Yong Gong

  DOI：10.1021/ja00092a055

  日期：1994.6

  [beta]-Si(CH[sub 3])[sub 3] moieties on the free energies of C-H homolysis and C-H heterolysis, for variously substituted fluorenes dissolved in dimethyl sulfoxide (DMSO). Analyses of these data indicate that replacement of a 9-H atom in fluorene with the [beta]-silicon-containing 9-(trimethylsilyl)methyl moiety reduces the 9C-H heterolysis free energy by 16 kcal/mol. This and other comparisons provide

  本通讯中包含第一个实验得出的热力学数据，可以比较 α- 和 β-Si(CH[sub 3])[sub 3] 部分对 CH 均裂和 CH 的自由能的影响杂解，用于溶解在二甲基亚砜（DMSO）中的各种取代芴。这些数据的分析表明，用含β-硅的9-(三甲基甲硅烷基)甲基部分取代芴中的9-H原子使9C-H杂解自由能降低16kcal/mol。这种比较和其他比较为 Si[sup +]/C=C 超共轭的重要性提供了基于热力学的实验基础，因为它与溶液相碳正离子稳定有关。18 个参考文献，1 个标签。
• β-Silyl Effects on the Stabilities of Carbanions and Carbon-Centered Radicals Derived from Ethyl Thionacetates, Diethyl Malonates, and Ethyl Acetoacetates
  作者：Shizhong Zhang、Frederick G. Bordwell

  DOI：10.1021/jo951506g

  日期：1996.1.1

  The effects of an alpha-Me(3)SiCH(2) group on the equilibrium acidities in DMSO of the acidic C-H bonds in esters, including ethyl thionacetate, diethyl malonate, and ethyl acetoacetate, were found to differ from that of an alpha-MeCH(2) group by less than 1 kcal/mol, pointing to little or no stabilizing effect of a beta-Me(3)Si group on carbanion stabilities. On the other hand, substitution of an alpha-Me(3)SiCH(2) group for one of the acidic hydrogen atoms in these esters to give Me(3)SiCH(2)CH(2)C(=S)OEt, Me(3)SiCH(2)CH(CO(2)Et)(2), and Me(3)SiCH(2)CH(CO(2)Et)COCH3 was found to decrease the homolytic bond dissociation energies (BDEs) of the remaining acidic C-H bonds by 7.1, 8.2, and 7.1 kcal/mol, respectively, relative to those of the parent esters and by 2.7, 4.5, and 4.4 kcal/mol, respectively, relative to the BDEs of the acidic C-H bonds in the corresponding MeCH(2)-substituted esters. The differences in BDEs observed between the Me(3)SiCH(2)- and the MeCH(2)-substituted ester derivatives are indicative of the presence of 3-5 kcal/mol C-H bond stabilizing effects of beta-Me(3)Si groups, relative to those of beta-Me groups, on the corresponding carbon radicals. The BDE value of the acidic C-H bond in Me3(C)CH(2)CH(2)C(=S)OEt was found to be 86.4 kcal/mol, which represents a 0.6 kcal/mol increase in BDE relative to that of the acidic C-H bond in MeCH(2)CH(2)C(=S)OEt. This result demonstrates the absence of a stabilizing effect of a beta-tert-butyl group on an open-chain carbon-centered radical. This is contrary to an apparent 6.4 kcal/mol C-H bond stabilizing effect of the beta-tert-butyl group in 9-neopentylfluorene, relative to that in fluorene, which is attributed to the relief of steric strain in forming the radical.