methyl 2,4,4-trimethyl-3-trimethylsilyloxypentanoate | 127015-44-5

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 脂肪酰基
• 英文名称: methyl 2,4,4-trimethyl-3-trimethylsilyloxypentanoate
• CAS: 127015-44-5；127015-45-6；136425-73-5；136425-81-5
• 化学式: C₁₂H₂₆O₃Si
• 分子量: 246.422
• InChiKey: LDZZYAVTAGGMKD-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.06
• 重原子数：
  16.0
• 可旋转键数：
  4.0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.92
• 拓扑面积：
  35.53
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  methyl 2,4,4-trimethyl-3-trimethylsilyloxypentanoate 在 四丁基氟化铵 作用下， 以 四氢呋喃 、 水 为溶剂， 生成 anti-methyl 3-hydroxy-2,4,4-trimethylpentanoate 、 syn-methyl 3-hydroxy-2,4,4-trimethylpentanoate
  参考文献：
  名称：

  Mukaiyama Aldol Reactions Catalyzed by Zirconocene Bis(triflate) Complexes:  Stereochemistry and Mechanisms for C−C Bond Formation

  摘要：

  The aldol condensations of alpha- and beta-(benzyloxy) aldehydes with enol silanes, catalyzed by Cp2Zr(OTf)(2) . THF or Cp2Zr(OTf)(2), in a variety of solvents were studied. The simple diastereoselectivity of these reactions is modest and comparable to that observed using simple aldehydes of similar steric requirements. Studies have revealed that TMSOTf is directly produced on reaction with the zirconocene catalyst with the enol silane in nitroalkane solvent or is formed during catalysis in dichloromethane solution. Although TMSOTf is known to catalyze cross-aldol reactions under these conditions, the rate of this process is not always competitive with that observed using the zircanocene catalysts. In particular, sterically unhindered or aromatic aldehydes react via a mechanism that appears to be mainly Zr-catalyzed, based on both the difference in rate between Zr- and Si-mediated reactions as well as differences in enol silane/silyl triflate reactivity in crossover-type experiments. With sterically hindered aldehydes in dichloromethane or nitromethane, catalysis is mediated by Si. The Zr-catalyzed process occurs via formation of a Zr-aldolate complex from aldehyde and enol silane, with liberation of TMSOTf, followed by rate-limiting O-silylatian of the metal aldolate by TMSOTf, as revealed by both model studies and in situ monitoring during catalysis.

  DOI：

  10.1021/jo971803g
• 作为产物：
  描述：

  (E)-(1-methoxyprop-1-enyloxy)trimethylsilane 、 特戊醛 在 zirconocene bis(triflate) tetrahydrofuran complex 作用下， 以 various solvent(s) 为溶剂， 反应 1.5h， 以97%的产率得到methyl 2,4,4-trimethyl-3-trimethylsilyloxypentanoate
  参考文献：
  名称：

  Mukaiyama Aldol Reactions Catalyzed by Zirconocene Bis(triflate) Complexes:  Stereochemistry and Mechanisms for C−C Bond Formation

  摘要：

  The aldol condensations of alpha- and beta-(benzyloxy) aldehydes with enol silanes, catalyzed by Cp2Zr(OTf)(2) . THF or Cp2Zr(OTf)(2), in a variety of solvents were studied. The simple diastereoselectivity of these reactions is modest and comparable to that observed using simple aldehydes of similar steric requirements. Studies have revealed that TMSOTf is directly produced on reaction with the zirconocene catalyst with the enol silane in nitroalkane solvent or is formed during catalysis in dichloromethane solution. Although TMSOTf is known to catalyze cross-aldol reactions under these conditions, the rate of this process is not always competitive with that observed using the zircanocene catalysts. In particular, sterically unhindered or aromatic aldehydes react via a mechanism that appears to be mainly Zr-catalyzed, based on both the difference in rate between Zr- and Si-mediated reactions as well as differences in enol silane/silyl triflate reactivity in crossover-type experiments. With sterically hindered aldehydes in dichloromethane or nitromethane, catalysis is mediated by Si. The Zr-catalyzed process occurs via formation of a Zr-aldolate complex from aldehyde and enol silane, with liberation of TMSOTf, followed by rate-limiting O-silylatian of the metal aldolate by TMSOTf, as revealed by both model studies and in situ monitoring during catalysis.

  DOI：

  10.1021/jo971803g

文献信息

• [1,2-Benzenediolato(2−)-<i>O</i>-<i>O</i>′]oxotitanium. A Chemoselective and Efficient Catalyst for Aldol-type Reaction of Ketene Silyl Acetals with Aldehydes
  作者：Ryuichiro Hara、Teruaki Mukaiyama

  DOI：10.1246/cl.1989.1909

  日期：1989.11

  In the presence of a catalytic amount of [1,2-benzenediolato(2−)-O,O′]oxotitanium, ketene silyl acetals smoothly react with aldehydes to afford the corresponding β-hydroxy carboxylic esters in good yields under mild conditions. According to this procedure, an aldehyde group is selectively activated, while an acid labile acetal group remains intact.

  在少量[1,2-苯二醇酸(2−)-O,O']氧合钛的催化下，酮烯硅缩醛能在温和条件下顺利与醛反应，以良好产率得到相应的β-羟基羧酸酯。根据这一方法，醛基被选择性激活，而酸敏性的缩醛基团保持不变。