p-tolyl((trimethylsilyl)oxy)methylium | 135189-84-3

• 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: p-tolyl((trimethylsilyl)oxy)methylium
• CAS: 135189-84-3
• 化学式: C₁₁H₁₇OSi
• 分子量: 193.341
• InChiKey: WWOZFMGYIFJOIG-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.36
• 重原子数：
  13.0
• 可旋转键数：
  3.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.36
• 拓扑面积：
  9.23
• 氢给体数：
  0.0
• 氢受体数：
  1.0

反应信息

• 作为反应物：
  描述：

  p-tolyl((trimethylsilyl)oxy)methylium 在 2,2,2-三氟乙醇 作用下， 生成 对甲基苯甲醛
  参考文献：
  名称：

  Production of α-Siloxycarbenium Ions by Protonation of Photochemically Generated α-Siloxycarbenes. Formation Mechanism and Reactivities with Nucleophiles

  摘要：

  The acyltrimethylsilanes 4-RC(6)H(4)C(O)SiMe(3) (R = H, Me, MeO) and beta-naphthylC(O)SiMe(3), upon photolysis in acetonitrile with 20 ns pulses of 248 nm light from an KrF* excimer laser, give rise to the corresponding alpha-siloxycarbenes ArC:OSiMe(3), whose absorption spectra (lambda(max) between 270 and 310 nm), lifetimes (between 130 and 260 ns), and reactivities with proton donors (ROH, mainly alcohols) are reported. With highly acidic ROH, such as 1,1,1,3,3,3-hexafluoroisopropyl alcohol (HFIP), the reaction is of simple second order, rate constants being in the 10(9) M(-1) s(-1) range and virtually independent of the nature of the aromatic moiety of the carbene. Isotopic substitution of H in ROH by D has no effect on the rate constant for reaction with carbene. For less acidic alcohols such as, e.g., methanol, the reactivity of the carbenes increases with increasing [ROH]. This behavior is interpreted in terms of reversible adduct formation between carbene and alcohol followed by reaction with further alcohol molecule(s) to give product. On the basis of experiments in the acidic and only weakly nucleophilic solvents 2,2,2-trifluorethanol (TFE) and HFIP, protonation of the carbenes leads to the corresponding carbenium ions, whose absorption spectra (lambda(max) between 305 and 355 nm), Lifetimes (100 ns-5 mu s in TFE), and reactivities with nucleophiles (halides, alcohols, and ethers) are reported. In the solvent HFIP, the reactivities of the carbenium ions with the alcohols and ethers increase with their concentration, in a way analogous to that observed in the reaction of the carbenes with the alcohols. This is explained as resulting from reversible formation of a cation-nucleophile complex followed by reaction of the complex with a second nucleophile molecule which acts as a base. In solvents more basic than HFIP, it is presumably the solvent which serves this function.

  DOI：

  10.1021/ja9603970
• 作为产物：
  描述：

  C₁₁H₁₆OSi 在 甲醇 作用下， 以 乙腈 为溶剂， 生成 p-tolyl((trimethylsilyl)oxy)methylium
  参考文献：
  名称：

  Production of α-Siloxycarbenium Ions by Protonation of Photochemically Generated α-Siloxycarbenes. Formation Mechanism and Reactivities with Nucleophiles

  摘要：

  The acyltrimethylsilanes 4-RC(6)H(4)C(O)SiMe(3) (R = H, Me, MeO) and beta-naphthylC(O)SiMe(3), upon photolysis in acetonitrile with 20 ns pulses of 248 nm light from an KrF* excimer laser, give rise to the corresponding alpha-siloxycarbenes ArC:OSiMe(3), whose absorption spectra (lambda(max) between 270 and 310 nm), lifetimes (between 130 and 260 ns), and reactivities with proton donors (ROH, mainly alcohols) are reported. With highly acidic ROH, such as 1,1,1,3,3,3-hexafluoroisopropyl alcohol (HFIP), the reaction is of simple second order, rate constants being in the 10(9) M(-1) s(-1) range and virtually independent of the nature of the aromatic moiety of the carbene. Isotopic substitution of H in ROH by D has no effect on the rate constant for reaction with carbene. For less acidic alcohols such as, e.g., methanol, the reactivity of the carbenes increases with increasing [ROH]. This behavior is interpreted in terms of reversible adduct formation between carbene and alcohol followed by reaction with further alcohol molecule(s) to give product. On the basis of experiments in the acidic and only weakly nucleophilic solvents 2,2,2-trifluorethanol (TFE) and HFIP, protonation of the carbenes leads to the corresponding carbenium ions, whose absorption spectra (lambda(max) between 305 and 355 nm), Lifetimes (100 ns-5 mu s in TFE), and reactivities with nucleophiles (halides, alcohols, and ethers) are reported. In the solvent HFIP, the reactivities of the carbenium ions with the alcohols and ethers increase with their concentration, in a way analogous to that observed in the reaction of the carbenes with the alcohols. This is explained as resulting from reversible formation of a cation-nucleophile complex followed by reaction of the complex with a second nucleophile molecule which acts as a base. In solvents more basic than HFIP, it is presumably the solvent which serves this function.

  DOI：

  10.1021/ja9603970

文献信息

• Binding Interaction of the Trimethylsilyl Cation with Oxygen and Nitrogen Bases in the Gas Phase. Acetopheones, Benzaldehydes, Pyridines, Anilines, and<b><i>N</i></b>,<b><i>N</i></b>-Dimethylanilines
  作者：Mustanir、Kenji Shimada、Fumio Ohta、Masaaki Mishima

  DOI：10.1246/bcsj.73.1845

  日期：2000.8

  benzaldehyde < acetophenone < aniline < pyridine < N,N-dimethylaniline. The effects of ring substituents on the GB(Me3Si+) of the respective bases are, however, linearly correlated with the corresponding proton basicities with a slope of 0.8 to 1.0, showing family-dependent linear relationships. Furthermore, an analysis of the substituent effects on the GB(Me3Si+) of acetophenone and benzaldehyde showed

  通过测量三甲基甲硅烷基阳离子转移反应的平衡常数，确定了一系列苯乙酮、苯甲醛、吡啶、苯胺和 N，N-二甲基苯胺对三甲基甲硅烷基阳离子 GB(Me3Si+) 的气相碱性。GB(Me3Si+) 增加的顺序是苯胺 < 苯甲醛 < 苯乙酮 < N,N-二甲基苯胺 < 吡啶，而 GB(H+) 增加的顺序是苯甲醛 < 苯乙酮 < 苯胺 < 吡啶 < N,N-二甲基苯胺。然而，环取代基对各个碱基的 GB(Me3Si+) 的影响与相应的质子碱度呈线性相关，斜率为 0.8 至 1.0，显示出家族相关的线性关系。此外，对苯乙酮和苯甲醛的 GB(Me3Si+) 的取代基效应的分析表明，ρ 值接近质子碱度的值，尽管与质子化离子相比，Me3Si+ 加合物离子的共振需求略有降低。B3LYP/6-31+G(d) 下的 DFT 计算......