methyl (1S)-1-(4-bromophenyl)-2-propan-2-ylidenecyclopropane-1-carboxylate | 1187852-64-7

• 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: methyl (1S)-1-(4-bromophenyl)-2-propan-2-ylidenecyclopropane-1-carboxylate
• CAS: 1187852-64-7
• 化学式: C₁₄H₁₅BrO₂
• 分子量: 295.176
• InChiKey: WMIXUXZAQIFJQT-AWEZNQCLSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.6
• 重原子数：
  17
• 可旋转键数：
  3
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.36
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  3-甲基-1,2-丁二烯 、 methyl 2-(4-bromophenyl)-2-diazoacetate 在 Rh₂[(N-(4-dodecylphenyl)sulfonyl)-(S)-prolinate]4 作用下， 以 正己烷 为溶剂， 以38%的产率得到methyl (1S)-1-(4-bromophenyl)-2-propan-2-ylidenecyclopropane-1-carboxylate
  参考文献：
  名称：

  Rhodium-Mediated Enantioselective Cyclopropanation of Allenes

  摘要：

  Reaction of monosubstituted allenes with aryldiazoacetate esters under dirhodium tetracarboxylate catalysis led to alkylidene cyclopropane products in 80-90% ee. Monosubstituted alkyl- and arylallene substrates gave 60-75% yield under standard conditions, while yields for 1,1-disubstituted allenes were significantly lower. Cyclopropanation of 1-methyl-1-(trimethylsilyl)allene proceeded in higher yield than other 1,1-disubstituted substrates, suggesting rate enhancement mediated by a significant beta-silicon effect.

  DOI：

  10.1021/ol9017968

文献信息

• Substituent effects on rates of rhodium-catalyzed allene cyclopropanation
  作者：Timothy M. Gregg、Russell F. Algera、John R. Frost、Furqan Hassan、Robert J. Stewart

  DOI：10.1016/j.tetlet.2010.09.143

  日期：2010.12

  cyclopropanations. Relative reaction rates for aliphatic allenes were found to be similar to those for aryl-substituted allenes, but silicon substitution was found to give a 5- to 14-fold rate increase. The rate enhancement effect for 1-silyl allenes can partially make up for loss of rate and regioselectivity, with 1-trimethylsilyl-1,2-butadiene exhibiting high levels of enantioselectivity and diastereoselectivity

  已经测量了与Rh 2（S- DOSP）4催化的芳基重氮乙酸酯反应时，相对于标准底物，单-和双取代的烯丙基的环丙烷化速率。苯丙二烯衍生物的速率与σ +呈线性关系系数，表明基于共振的效应，尽管对艾伦而言，效应的幅度小于对其他环丙烷的报道。发现脂族丙二烯的相对反应速率与芳基取代的丙二烯的相对反应速率相似，但是发现硅取代使速率增加5至14倍。1-甲硅烷基丙二烯的速率增强作用可以部分弥补速率和区域选择性的损失，其中1-三甲基甲硅烷基-1,2-丁二烯在与手性催化剂反应中表现出高水平的对映选择性和非对映选择性。
• Rhodium-Mediated Enantioselective Cyclopropanation of Allenes
  作者：Timothy M. Gregg、Mark K. Farrugia、John R. Frost

  DOI：10.1021/ol9017968

  日期：2009.10.1

  Reaction of monosubstituted allenes with aryldiazoacetate esters under dirhodium tetracarboxylate catalysis led to alkylidene cyclopropane products in 80-90% ee. Monosubstituted alkyl- and arylallene substrates gave 60-75% yield under standard conditions, while yields for 1,1-disubstituted allenes were significantly lower. Cyclopropanation of 1-methyl-1-(trimethylsilyl)allene proceeded in higher yield than other 1,1-disubstituted substrates, suggesting rate enhancement mediated by a significant beta-silicon effect.