(2R,3E)-2-(benzoyloxy)-4-(4-methoxyphenyl)but-3-enenitrile | 1347042-66-3

• 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: (2R,3E)-2-(benzoyloxy)-4-(4-methoxyphenyl)but-3-enenitrile
• CAS: 1347042-66-3
• 化学式: C₁₈H₁₅NO₃
• 分子量: 293.322
• InChiKey: VHVWOYYHUJHBMM-XLNAKTSKSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.46
• 重原子数：
  22.0
• 可旋转键数：
  5.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.11
• 拓扑面积：
  59.32
• 氢给体数：
  0.0
• 氢受体数：
  4.0

反应信息

• 作为产物：
  描述：

  苯甲酰腈 、 4-甲氧基肉桂醛 在 titanium(IV) isopropylate 、 (S)-3,3'-bis[(diethylamino)methyl]-2,2'-dihydroxy-1,1'-binaphthalene 作用下， 以 四氢呋喃 为溶剂， 反应 60.0h， 生成 (2S,3E)-2-(benzoyloxy)-4-(4-methoxyphenyl)but-3-enenitrile 、 (2R,3E)-2-(benzoyloxy)-4-(4-methoxyphenyl)but-3-enenitrile
  参考文献：
  名称：

  Mechanistic studies on the enantioselective BINOLAM/titanium(IV)-catalyzed cyanobenzoylation of aldehydes: Part 1

  摘要：

  The enantioselective titanium(IV)-catalyzed cyanobenzoylation of aldehydes using 1:1 BINOLAM/Ti(OiPr)(4) mixtures as a precatalyst gave O-aroyl cyanohydrins 4 with good enantiomeric excesses. The standard optimization set carried out on the assumption of Curtin-Hammett behavior, led to no amelioration.Extensive experimental and computational studies were carried out with the purpose of identifying the key mechanistic aspects governing enantioselectivity. HCN and isopropyl benzoate were detected in the reacting mixtures. This as well as the reaction response to the presence of an exogenous base, and the failure to react in the presence of Binol/Ti(OiPr)(4) mixtures, led us to propose, not a direct but an indirect process involving an enantioselective hydrocyanation step by O-benzoylation. Computational work carried out with mononuclear monomeric M-M and dinuclear mixed dimer D-IMD as catalysts support this mechanistic proposal.On the other hand, cyanobenzoylations carried out with 1:2 or higher 1:n (up to 1:5) BINOLAM/Ti(OiPr)(4) mixtures appear to involve a reversal of the enantioselection. This, together with the fact that the benzoylation of the ligated iPrOH is a slow reaction, has led us to conclude that these cyanobenzoylations do not fit within the standard Curtin-Hammett kinetic scheme. Instead, such BINOLAM/Ti(O/Pr)(4)-catalyzed cyanobenzoylations of aldehydes rather behave as non-Curtin-Hammett kinetic schemes. Further computational analysis is needed in order to make a clear distinction between Curtin-Hammett and non-Curtin-Hammett kinetic frameworks. (C) 2011 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tetasy.2011.07.006

文献信息

• Mechanistic studies on the enantioselective BINOLAM/titanium(IV)-catalyzed cyanobenzoylation of aldehydes: Part 1
  作者：Alejandro Baeza、Carmen Nájera、José M. Sansano、José M. Saá

  DOI：10.1016/j.tetasy.2011.07.006

  日期：2011.6

  The enantioselective titanium(IV)-catalyzed cyanobenzoylation of aldehydes using 1:1 BINOLAM/Ti(OiPr)(4) mixtures as a precatalyst gave O-aroyl cyanohydrins 4 with good enantiomeric excesses. The standard optimization set carried out on the assumption of Curtin-Hammett behavior, led to no amelioration.Extensive experimental and computational studies were carried out with the purpose of identifying the key mechanistic aspects governing enantioselectivity. HCN and isopropyl benzoate were detected in the reacting mixtures. This as well as the reaction response to the presence of an exogenous base, and the failure to react in the presence of Binol/Ti(OiPr)(4) mixtures, led us to propose, not a direct but an indirect process involving an enantioselective hydrocyanation step by O-benzoylation. Computational work carried out with mononuclear monomeric M-M and dinuclear mixed dimer D-IMD as catalysts support this mechanistic proposal.On the other hand, cyanobenzoylations carried out with 1:2 or higher 1:n (up to 1:5) BINOLAM/Ti(OiPr)(4) mixtures appear to involve a reversal of the enantioselection. This, together with the fact that the benzoylation of the ligated iPrOH is a slow reaction, has led us to conclude that these cyanobenzoylations do not fit within the standard Curtin-Hammett kinetic scheme. Instead, such BINOLAM/Ti(O/Pr)(4)-catalyzed cyanobenzoylations of aldehydes rather behave as non-Curtin-Hammett kinetic schemes. Further computational analysis is needed in order to make a clear distinction between Curtin-Hammett and non-Curtin-Hammett kinetic frameworks. (C) 2011 Elsevier Ltd. All rights reserved.