(Z)-5-(6-Oxo-cyclohex-1-enyl)-pent-2-enoic acid ethyl ester | 167156-46-9

• 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: (Z)-5-(6-Oxo-cyclohex-1-enyl)-pent-2-enoic acid ethyl ester
• 英文别名: ethyl 5-(6-oxocyclohexen-1-yl)pent-2-enoate
• CAS: 167156-46-9
• 化学式: C₁₃H₁₈O₃
• 分子量: 222.284
• InChiKey: CZJVULQTCGOFIW-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.57
• 重原子数：
  16.0
• 可旋转键数：
  5.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.54
• 拓扑面积：
  43.37
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  (Z)-5-(6-Oxo-cyclohex-1-enyl)-pent-2-enoic acid ethyl ester 在 9,10-二氰基蒽 、 三苯基膦 作用下， 以 水 、 N,N-二甲基甲酰胺 、 异丙醇 为溶剂， 以84%的产率得到(1R,3aR,7aR,8S)-4-Oxo-octahydro-1,3a-methano-indene-8-carboxylic acid ethyl ester
  参考文献：
  名称：

  Designing Photosystems for Harvesting Photons into Electrons by Sequential Electron-Transfer Processes:  Reversing the Reactivity Profiles of α,β-Unsaturated Ketones as Carbon Radical Precursor by One Electron Reductive β-Activation

  摘要：

  Two photosystems are developed to harvest visible-light photons into electrons via sequential electron transfer processes. Photosystem-A (PS-A) consisted of DCA as light harvesting electron acceptor and Ph3P as sacrificial electron donor, whereas photosystem-B (PS-B) employed DCA as usual electron acceptor, DMN as a primary electron donor, and ascorbic acid as a secondary and sacrificial election donor. alpha,beta-Unsaturated ketones are utilized as secondary electron acceptors. The design of these photosystems is based on the thermodynamic feasibility of electron transfer between each participating components. Electron transfer from DCA(.-) to alpha,beta-unsaturated ketones leads to their beta-activation as carbon centered radicals which cyclizes efficiently to tethered activated olefins. Cyclization with a nonactivated olefin is found to be moderate. The cyclization stereochemistries have been illustrated by studying the PET activation of 5 and 21. The exclusive trans-stereochemistry observed in 8 is explained by considering the thermodynamic, equilibration of initially formed syn-intermediate 10 from 5. The isolation of trace amount of 9 in this reaction substantiates the syn-intermediacy as primary intermediate which is further confirmed by the isolation of 25 from 21. Formation of 25 suggests that wherever the syn-intermediate is thermodynamically more stable, it invariably undergoes further cyclization to geometrically well-placed enolate double bond. An interesting observation is made by isolating 9 as a major product from the PET activation of 5 using PS-B. Stabilization of 10 by ascorbic acid is suggested to be the plausible explanation for this unusual observation. Radicals produced by the reductive beta-activation of alpha,beta-unsaturated ketones follow well established radical cyclization rules which is exemplified by studying the reactions of 39 and 40. Generality of these cyclizations is demonstrated from the PET reactions of 29-32. Synthesis of 49, an important structural framework of biologically active angularly fused triquinanes, from 48 is included in this study to demonstrate the varied applicability of this strategy.

  DOI：

  10.1021/ja9641564
• 作为产物：
  描述：

  2-Ethoxy-2,3,4,6,7,8-hexahydro-chromen-5-one 在 盐酸 、 lithium aluminium tetrahydride 作用下， 以 二氯甲烷 为溶剂， 反应 31.5h， 生成 (Z)-5-(6-Oxo-cyclohex-1-enyl)-pent-2-enoic acid ethyl ester
  参考文献：
  名称：

  Designing Photosystems for Harvesting Photons into Electrons by Sequential Electron-Transfer Processes:  Reversing the Reactivity Profiles of α,β-Unsaturated Ketones as Carbon Radical Precursor by One Electron Reductive β-Activation

  摘要：

  Two photosystems are developed to harvest visible-light photons into electrons via sequential electron transfer processes. Photosystem-A (PS-A) consisted of DCA as light harvesting electron acceptor and Ph3P as sacrificial electron donor, whereas photosystem-B (PS-B) employed DCA as usual electron acceptor, DMN as a primary electron donor, and ascorbic acid as a secondary and sacrificial election donor. alpha,beta-Unsaturated ketones are utilized as secondary electron acceptors. The design of these photosystems is based on the thermodynamic feasibility of electron transfer between each participating components. Electron transfer from DCA(.-) to alpha,beta-unsaturated ketones leads to their beta-activation as carbon centered radicals which cyclizes efficiently to tethered activated olefins. Cyclization with a nonactivated olefin is found to be moderate. The cyclization stereochemistries have been illustrated by studying the PET activation of 5 and 21. The exclusive trans-stereochemistry observed in 8 is explained by considering the thermodynamic, equilibration of initially formed syn-intermediate 10 from 5. The isolation of trace amount of 9 in this reaction substantiates the syn-intermediacy as primary intermediate which is further confirmed by the isolation of 25 from 21. Formation of 25 suggests that wherever the syn-intermediate is thermodynamically more stable, it invariably undergoes further cyclization to geometrically well-placed enolate double bond. An interesting observation is made by isolating 9 as a major product from the PET activation of 5 using PS-B. Stabilization of 10 by ascorbic acid is suggested to be the plausible explanation for this unusual observation. Radicals produced by the reductive beta-activation of alpha,beta-unsaturated ketones follow well established radical cyclization rules which is exemplified by studying the reactions of 39 and 40. Generality of these cyclizations is demonstrated from the PET reactions of 29-32. Synthesis of 49, an important structural framework of biologically active angularly fused triquinanes, from 48 is included in this study to demonstrate the varied applicability of this strategy.

  DOI：

  10.1021/ja9641564

文献信息

• Visible light initiated photosensitised electron transfer (PET) reductive β-activation of α,β-unsaturated ketones for radical cyclisation: A new concept in promoting radical reactions
  作者：Ganesh Pandey、Saumen Hajra、Manas K. Ghorai

  DOI：10.1016/0040-4039(94)80131-2

  日期：1994.10

  Photosensitised one electron reductive β-activation of α,β-unsaturated ketones for radical cyclisations are reported.

  据报道，α，β-不饱和酮的光敏化一种电子还原性β-活化作用可用于自由基环化反应。
• Designing Photosystems for Harvesting Photons into Electrons by Sequential Electron-Transfer Processes:  Reversing the Reactivity Profiles of α,β-Unsaturated Ketones as Carbon Radical Precursor by One Electron Reductive β-Activation
  作者：Ganesh Pandey、Saumen Hajra、Manas K. Ghorai、K. Ravi Kumar

  DOI：10.1021/ja9641564

  日期：1997.9.1

  Two photosystems are developed to harvest visible-light photons into electrons via sequential electron transfer processes. Photosystem-A (PS-A) consisted of DCA as light harvesting electron acceptor and Ph3P as sacrificial electron donor, whereas photosystem-B (PS-B) employed DCA as usual electron acceptor, DMN as a primary electron donor, and ascorbic acid as a secondary and sacrificial election donor. alpha,beta-Unsaturated ketones are utilized as secondary electron acceptors. The design of these photosystems is based on the thermodynamic feasibility of electron transfer between each participating components. Electron transfer from DCA(.-) to alpha,beta-unsaturated ketones leads to their beta-activation as carbon centered radicals which cyclizes efficiently to tethered activated olefins. Cyclization with a nonactivated olefin is found to be moderate. The cyclization stereochemistries have been illustrated by studying the PET activation of 5 and 21. The exclusive trans-stereochemistry observed in 8 is explained by considering the thermodynamic, equilibration of initially formed syn-intermediate 10 from 5. The isolation of trace amount of 9 in this reaction substantiates the syn-intermediacy as primary intermediate which is further confirmed by the isolation of 25 from 21. Formation of 25 suggests that wherever the syn-intermediate is thermodynamically more stable, it invariably undergoes further cyclization to geometrically well-placed enolate double bond. An interesting observation is made by isolating 9 as a major product from the PET activation of 5 using PS-B. Stabilization of 10 by ascorbic acid is suggested to be the plausible explanation for this unusual observation. Radicals produced by the reductive beta-activation of alpha,beta-unsaturated ketones follow well established radical cyclization rules which is exemplified by studying the reactions of 39 and 40. Generality of these cyclizations is demonstrated from the PET reactions of 29-32. Synthesis of 49, an important structural framework of biologically active angularly fused triquinanes, from 48 is included in this study to demonstrate the varied applicability of this strategy.