(4E)-4-(2-bromo-4,4-dimethylcyclohex-2-en-1-ylidene)-2,2-dimethylbutanoic acid | 423764-47-0

• 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: (4E)-4-(2-bromo-4,4-dimethylcyclohex-2-en-1-ylidene)-2,2-dimethylbutanoic acid
• CAS: 423764-47-0
• 化学式: C₁₄H₂₁BrO₂
• 分子量: 301.224
• InChiKey: FAMBSMGIMLZVHA-UXBLZVDNSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.2
• 重原子数：
  17
• 可旋转键数：
  3
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.64
• 拓扑面积：
  37.3
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (4E)-4-(2-bromo-4,4-dimethylcyclohex-2-en-1-ylidene)-2,2-dimethylbutanoic acid 在 正丁基锂 、 溶剂黄146 作用下， 以 四氢呋喃 、 正己烷 为溶剂， 反应 0.5h， 以81%的产率得到4-[4,4-Dimethyl-cyclohex-2-en-(E)-ylidene]-2,2-dimethyl-butyric acid
  参考文献：
  名称：

  Intramolecularly Competitive Ireland-Claisen Rearrangements:  Scope and Potential Applications to Natural Product Synthesis

  摘要：

  A variety of bis-allylic esters were prepared by vinylmetal addition to cycloalkenones followed by esterification either in situ or in a separate operation. For chiral cyclohexenones, the vinyl additions generally occurred with > 10:1 diastereoselectivity. Although in some cases the bis-allylic esters proved to be sensitive to silica gel or other adsorbents, all of the esters examined could be isolated in acceptable purity. The Ireland-Claisen rearrangement of the bis-allylic esters occurred with complete regioselectivity via the exocyclic alkene. The alkene stereochemistry and the stereochemistry at C-2 and C-3 of the pentenoic acid products were consistent with a chairlike transition state in the rearrangement. Substituents at the carbons adjacent to the allylic carbinol carbon (i.e., C-2 or C-6 in cyclohexenone-derived substrates) directed the stereochemical course of the rearrangement. The rearrangements generally proceeded so as to place the larger of the C-2 or C-6 substituents in the pseudoequatorial position with respect to the chairlike transition state. For a bis-allylic ester bearing both a C-2-CH3 and a C-6-OMEM substituent, the rearrangement product resulted from the nominally smaller OMEM substituent occupying a pseudoequatorial position with respect to the chairlike transition state.

  DOI：

  10.1021/jo010752r
• 作为产物：
  描述：

  2-溴-4,4-二甲基-2-环己烯-1-酮 在 乙烯基溴化镁 、 水 、 双(三甲基硅烷基)氨基钾 、 potassium carbonate 作用下， 以 四氢呋喃 、 甲醇 、 乙醚 、 甲苯 为溶剂， 反应 4.5h， 生成 (4E)-4-(2-bromo-4,4-dimethylcyclohex-2-en-1-ylidene)-2,2-dimethylbutanoic acid
  参考文献：
  名称：

  Intramolecularly Competitive Ireland-Claisen Rearrangements:  Scope and Potential Applications to Natural Product Synthesis

  摘要：

  A variety of bis-allylic esters were prepared by vinylmetal addition to cycloalkenones followed by esterification either in situ or in a separate operation. For chiral cyclohexenones, the vinyl additions generally occurred with > 10:1 diastereoselectivity. Although in some cases the bis-allylic esters proved to be sensitive to silica gel or other adsorbents, all of the esters examined could be isolated in acceptable purity. The Ireland-Claisen rearrangement of the bis-allylic esters occurred with complete regioselectivity via the exocyclic alkene. The alkene stereochemistry and the stereochemistry at C-2 and C-3 of the pentenoic acid products were consistent with a chairlike transition state in the rearrangement. Substituents at the carbons adjacent to the allylic carbinol carbon (i.e., C-2 or C-6 in cyclohexenone-derived substrates) directed the stereochemical course of the rearrangement. The rearrangements generally proceeded so as to place the larger of the C-2 or C-6 substituents in the pseudoequatorial position with respect to the chairlike transition state. For a bis-allylic ester bearing both a C-2-CH3 and a C-6-OMEM substituent, the rearrangement product resulted from the nominally smaller OMEM substituent occupying a pseudoequatorial position with respect to the chairlike transition state.

  DOI：

  10.1021/jo010752r

文献信息

• Intramolecularly Competitive Ireland-Claisen Rearrangements:  Scope and Potential Applications to Natural Product Synthesis
  作者：Sang-phyo Hong、Harriet A. Lindsay、Tripura Yaramasu、Xiaowei Zhang、Matthias C. McIntosh

  DOI：10.1021/jo010752r

  日期：2002.4.1

  A variety of bis-allylic esters were prepared by vinylmetal addition to cycloalkenones followed by esterification either in situ or in a separate operation. For chiral cyclohexenones, the vinyl additions generally occurred with > 10:1 diastereoselectivity. Although in some cases the bis-allylic esters proved to be sensitive to silica gel or other adsorbents, all of the esters examined could be isolated in acceptable purity. The Ireland-Claisen rearrangement of the bis-allylic esters occurred with complete regioselectivity via the exocyclic alkene. The alkene stereochemistry and the stereochemistry at C-2 and C-3 of the pentenoic acid products were consistent with a chairlike transition state in the rearrangement. Substituents at the carbons adjacent to the allylic carbinol carbon (i.e., C-2 or C-6 in cyclohexenone-derived substrates) directed the stereochemical course of the rearrangement. The rearrangements generally proceeded so as to place the larger of the C-2 or C-6 substituents in the pseudoequatorial position with respect to the chairlike transition state. For a bis-allylic ester bearing both a C-2-CH3 and a C-6-OMEM substituent, the rearrangement product resulted from the nominally smaller OMEM substituent occupying a pseudoequatorial position with respect to the chairlike transition state.