2-<(1S,2R,3R,4S)-2-Hydroxy-3-(methoxymethoxy)-7,7-dimethyl-1-vinyl-2-norbornyl>-2-cyclohexen-1-one | 162790-85-4

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 2-<(1S,2R,3R,4S)-2-Hydroxy-3-(methoxymethoxy)-7,7-dimethyl-1-vinyl-2-norbornyl>-2-cyclohexen-1-one
• 英文别名: 2-[(1S,2R,3R,4S)-1-ethenyl-2-hydroxy-3-(methoxymethoxy)-7,7-dimethyl-2-bicyclo[2.2.1]heptanyl]cyclohex-2-en-1-one
• CAS: 162790-85-4
• 化学式: C₁₉H₂₈O₄
• 分子量: 320.429
• InChiKey: ZHJJXAIEUJNBBK-YCEFEEMOSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.4
• 重原子数：
  23
• 可旋转键数：
  5
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.74
• 拓扑面积：
  55.8
• 氢给体数：
  1
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  硫酸二甲酯 、 2-<(1S,2R,3R,4S)-2-Hydroxy-3-(methoxymethoxy)-7,7-dimethyl-1-vinyl-2-norbornyl>-2-cyclohexen-1-one 在 potassium tert-butylate 作用下， 生成 (E)-(1S,2R,9R)-5-Methoxy-2-methoxymethoxy-15,15-dimethyl-tricyclo[10.2.1.0^4,9]pentadeca-4,11-dien-3-one
  参考文献：
  名称：

  Evaluation of 2-Bromocyclohexenone Acetals as Vehicles for the Introduction of C-7 Oxygen Preliminary to the Synthesis of Taxane Diterpenes

  摘要：

  The coupling of an optically pure, camphor-derived, beta,gamma-unsaturated, bicyclic ketone with a suitable vinyl organometallic is recognized to result in 1,2-addition from the endo face. Anionic oxy-Cope rearrangement of these carbinols proceeds via an ''endo-chair'' transition state to deliver a strained and reactive enolate that is formed regioselectively and is amenable to alpha-methylation from the top face. These steps, which are preliminary to a broad-based approach to the taxane diterpenes, had not yet accommodated suitable introduction of a C-7 oxygen substituent as required of taxol. Typically, an ether substituent at this site experiences beta-elimination once the enolate anion intermediate is accessed. Herein it is demonstrated that the parent 2-bromocyclohexenone acetal is well suited to resolving this complication. Halogen-metal exchange proceeds well to provide a suitably nucleophilic building block. Direct charge-accelerated sigmatropic rearrangement of the carbinol products does proceed with beta-elimination, but under the present circumstances the second C-O bond remains in the form of a vinylogous ester. Alternatively, the carbinols are amenable to chemoselective hydrolysis of the acetal, thereby unmasking a conjugated cyclohexenone part structure. These intermediates have been found to rearrange along completely analogous reaction trajectories to provide enolates of a beta-diketone subunit. The extent to which these anions undergo C- versus O-methylation under various conditions has been examined. When O-methylation does occur, it is the C-7 oxygen (and not the one at C-9) that is engaged in reaction.

  DOI：

  10.1021/jo00109a021
• 作为产物：
  描述：

  (1S,2R,3R,4S)-2-(1,4-Dioxaspiro<4.5>dec-6-en-6-yl)-3-(methoxymethoxy)-7,7-dimethyl-1-vinyl-2-norbornanol 在 4-甲基苯磺酸吡啶 作用下， 以 丙酮 为溶剂， 反应 1.5h， 以100%的产率得到2-<(1S,2R,3R,4S)-2-Hydroxy-3-(methoxymethoxy)-7,7-dimethyl-1-vinyl-2-norbornyl>-2-cyclohexen-1-one
  参考文献：
  名称：

  Evaluation of 2-Bromocyclohexenone Acetals as Vehicles for the Introduction of C-7 Oxygen Preliminary to the Synthesis of Taxane Diterpenes

  摘要：

  The coupling of an optically pure, camphor-derived, beta,gamma-unsaturated, bicyclic ketone with a suitable vinyl organometallic is recognized to result in 1,2-addition from the endo face. Anionic oxy-Cope rearrangement of these carbinols proceeds via an ''endo-chair'' transition state to deliver a strained and reactive enolate that is formed regioselectively and is amenable to alpha-methylation from the top face. These steps, which are preliminary to a broad-based approach to the taxane diterpenes, had not yet accommodated suitable introduction of a C-7 oxygen substituent as required of taxol. Typically, an ether substituent at this site experiences beta-elimination once the enolate anion intermediate is accessed. Herein it is demonstrated that the parent 2-bromocyclohexenone acetal is well suited to resolving this complication. Halogen-metal exchange proceeds well to provide a suitably nucleophilic building block. Direct charge-accelerated sigmatropic rearrangement of the carbinol products does proceed with beta-elimination, but under the present circumstances the second C-O bond remains in the form of a vinylogous ester. Alternatively, the carbinols are amenable to chemoselective hydrolysis of the acetal, thereby unmasking a conjugated cyclohexenone part structure. These intermediates have been found to rearrange along completely analogous reaction trajectories to provide enolates of a beta-diketone subunit. The extent to which these anions undergo C- versus O-methylation under various conditions has been examined. When O-methylation does occur, it is the C-7 oxygen (and not the one at C-9) that is engaged in reaction.

  DOI：

  10.1021/jo00109a021