(α-methylbenzyl) (2-ethyl-1-hexyl) ether

• 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: (α-methylbenzyl) (2-ethyl-1-hexyl) ether
• 英文别名: 1-Phenylethanol, 2-methylbutyl ether；1-(2-methylbutoxy)ethylbenzene
• 化学式: C₁₃H₂₀O
• 分子量: 192.301
• InChiKey: VDNSHTYXGSKAKY-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.7
• 重原子数：
  14
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.54
• 拓扑面积：
  9.2
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为产物：
  描述：

  2-甲基丁醇 、 苏合香醇 在 bismuth(III) bromide 作用下， 以 四氯化碳 为溶剂， 反应 0.25h， 以95%的产率得到(α-methylbenzyl) (2-ethyl-1-hexyl) ether
  参考文献：
  名称：

  BiBr3, an efficient catalyst for the benzylation of alcohols: 2-phenyl-2-propyl, a new benzyl-type protecting group

  摘要：

  The benzylation of aliphatic alcohols with various benzylic alcohols has been achieved in the presence of BiBr3 under mild conditions. 2-Phenylpropan-2-ol proved to be the most efficient and can be considered as a novel protecting group. (C) 2000 Elsevier Science Ltd. All rights reserved.

  DOI：

  10.1016/s0040-4039(00)00304-x

文献信息

• Biphasic Synthesis of 2-Phenylpropionic Acid and Ester by Interfacial Carbonylation of α-Methylbenzyl Bromide
  作者：Carnley Norman、Benjamin A. Wilhite、Duc Pham、Phooi K. Lim、Philip A. Brown

  DOI：10.1021/op9701292

  日期：1998.11.1

  An interfacial synthesis technique has been successfully extended to the carbonylation of alpha-methylbenzyl bromide in an organic-aqueous sodium hydroxide mixture at 35-60 degrees C and 1 atm using surface-active palladium - (4-dimethylaminophenyl)diphenylphosphine complex as the catalyst and dodecyl sodium sulfate as the emulsifier. Depending on the reaction conditions, 2-phenylpropionate in the form of sodium salt and an ester was obtained in 0-83% yield, along with varying amounts of side products that included alpha-methylbenzyl alcohol, 2,3 diphenylbutane, di(alpha-methylbenzyl)ether, and an asymmetric ether derived from the substrate and an alcoholic medium. When 2-methyl-1-butanol or 2-ethyl-1-hexanol was used as the organic phase, 2-phenylpropionate ester and sodium salt were obtained in 40-83% yield, with a maximum yield obtained at an optimal aqueous base concentration of about 5 M. At a lower aqueous base concentration, more of alpha-methylbenzyl alcohol was formed, whereas at a higher aqueous base concentration, more of 2,3-diphenylbutane and asymmetric ether were formed. When toluene was used as the organic phase, 2-phenylpropionate salt was obtained in less than 13% yield, and the major side product was a-methylbenzyl alcohol at a low aqueous base concentration and 2,3-diphenylbutane at a high aqueous base concentration. In all cases, the formation of 2,3-diphenylbutane was accompanied by a stoichiometric formation of carbonate. The latter implicates the involvement of an oxidative intermediate-tentatively identified as hypobromous acid-that could deactivate the catalyst complex through ligand degradation. Along with the carbonylation reaction, carbon monoxide also underwent a slow, base-induced hydrolysis reaction to form formic acid. With 2-ethyl-1-hexanol as the organic phase, the carbonylation of alpha-methylbenzyl bromide showed an apparent temperature-dependent activation energy, a first-order dependence each on the substrate, catalyst, and ligand concentrations up to the catalyst concentration of 0.0020 M and a ligand:catalyst ratio of 3:1, and a variable-order dependence on the carbon monoxide pressure that switched from first to zeroth order as the carbon monoxide pressure was increased above 450 mmHg. A reaction mechanism is proposed which yields model rate and yield expressions in accord with the experimental findings. Results of control experiments with alpha,alpha-dibromotoluene in a toluene-aqueous sodium hydroxide mixture indicate that replacement of the alpha-methyl group in alpha-methylbenzyl bromide by a second bromo group suppressed the formation of substituted benzyl alcohol and coupled product. They suggest that the broad product distribution in the carbonylation of alpha-methylbenzyl bromide relative to the carbonylation of benzyl chloride and alpha,alpha-dibromotoluene is attributable to the electron-releasing alpha-methyl group making the substrate susceptible to hydrolysis and coupling reactions.
• BiBr3, an efficient catalyst for the benzylation of alcohols: 2-phenyl-2-propyl, a new benzyl-type protecting group
  作者：Bernard Boyer、El-Mehdi Keramane、Jean-Pierre Roque、André A Pavia

  DOI：10.1016/s0040-4039(00)00304-x

  日期：2000.4

  The benzylation of aliphatic alcohols with various benzylic alcohols has been achieved in the presence of BiBr3 under mild conditions. 2-Phenylpropan-2-ol proved to be the most efficient and can be considered as a novel protecting group. (C) 2000 Elsevier Science Ltd. All rights reserved.