3(R)-isopropyl-1-methylcyclopentene | 2698-97-7

• 分子结构分类: 有机化合物 - 碳氢化合物 - 不饱和烃
• 英文名称: 3(R)-isopropyl-1-methylcyclopentene
• 英文别名: 3-Isopropyl-1-methyl-cyclopentene；(3R)-1-methyl-3-propan-2-ylcyclopentene
• CAS: 2698-97-7
• 化学式: C₉H₁₆
• 分子量: 124.226
• InChiKey: IAXQPFXJHAXENM-VIFPVBQESA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3
• 重原子数：
  9
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.78
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为反应物：
  描述：

  3-benzoyloxy-2-cyclopenten-1-one 、 3(R)-isopropyl-1-methylcyclopentene 以 苯甲腈 、 乙腈 为溶剂， 反应 21.0h， 生成 (1S,2R,6R,7R,8R)-6-(benzoyloxy)-8-isopropyl-1-methyltricyclo<5.3.0.0^2,6>-3-decanone 、 (1S,2S,6R,7S,10R)-6-(benzoyloxy)-10-isopropyl-7-methyltricyclo<5.3.0.0^2,6>-3-decanone
  参考文献：
  名称：

  A short enantiospecific route to isodaucane sesquiterpenes from limonene. On the absolute configuration of (+)-aphanamol I and II.

  摘要：

  The isodaucane sesquiterpenes (+)-aphanamol I (3) and (-)-2-oxoisodauc-5-en-12-al [(-)-6] have been prepared in a short reaction sequence from 5(S)-isopropyl-2-methyl-l-cyclopentene-1-carbaldehyde (S)-23 (readily obtainable from (+)-limonene). Key steps were a de Mayo type photocyclization of an 3-acyloxy-2-cyclopenten-1-one with 3(S)-isopropyl-1-methylcyclopentene [(S)-24] to a [5.3.0.0(2.6)]tricyclodecanone (e.g., (-)-28) with the desired configuration at all stereocenters and the formation of 3 by a base-catalyzed fragmentation of the gamma,delta-epoxyalcohol intermediate 33 (R = H), which produced all the desired functional groups in one step. The stereochemical assignments were supported by CD data as well as by the synthesis of (-)-norbourbonone (29) from (S)-24, which is a novel chiral intermediate. These results are in confliction with some earlier assignmnents of the absolute configuration in the isodaucane group of sesquiterpenes.

  DOI：

  10.1021/jo00046a018
• 作为产物：
  描述：

  (3R)-1-iriden-7-al 在 Wilkinson's catalyst 作用下， 以 苯甲腈 为溶剂， 反应 1.5h， 生成 3(R)-isopropyl-1-methylcyclopentene
  参考文献：
  名称：

  A short enantiospecific route to isodaucane sesquiterpenes from limonene. On the absolute configuration of (+)-aphanamol I and II.

  摘要：

  The isodaucane sesquiterpenes (+)-aphanamol I (3) and (-)-2-oxoisodauc-5-en-12-al [(-)-6] have been prepared in a short reaction sequence from 5(S)-isopropyl-2-methyl-l-cyclopentene-1-carbaldehyde (S)-23 (readily obtainable from (+)-limonene). Key steps were a de Mayo type photocyclization of an 3-acyloxy-2-cyclopenten-1-one with 3(S)-isopropyl-1-methylcyclopentene [(S)-24] to a [5.3.0.0(2.6)]tricyclodecanone (e.g., (-)-28) with the desired configuration at all stereocenters and the formation of 3 by a base-catalyzed fragmentation of the gamma,delta-epoxyalcohol intermediate 33 (R = H), which produced all the desired functional groups in one step. The stereochemical assignments were supported by CD data as well as by the synthesis of (-)-norbourbonone (29) from (S)-24, which is a novel chiral intermediate. These results are in confliction with some earlier assignmnents of the absolute configuration in the isodaucane group of sesquiterpenes.

  DOI：

  10.1021/jo00046a018

文献信息

• A short enantiospecific route to isodaucane sesquiterpenes from limonene. On the absolute configuration of (+)-aphanamol I and II.
  作者：Thomas Hansson、Boerje Wickberg

  DOI：10.1021/jo00046a018

  日期：1992.9

  The isodaucane sesquiterpenes (+)-aphanamol I (3) and (-)-2-oxoisodauc-5-en-12-al [(-)-6] have been prepared in a short reaction sequence from 5(S)-isopropyl-2-methyl-l-cyclopentene-1-carbaldehyde (S)-23 (readily obtainable from (+)-limonene). Key steps were a de Mayo type photocyclization of an 3-acyloxy-2-cyclopenten-1-one with 3(S)-isopropyl-1-methylcyclopentene [(S)-24] to a [5.3.0.0(2.6)]tricyclodecanone (e.g., (-)-28) with the desired configuration at all stereocenters and the formation of 3 by a base-catalyzed fragmentation of the gamma,delta-epoxyalcohol intermediate 33 (R = H), which produced all the desired functional groups in one step. The stereochemical assignments were supported by CD data as well as by the synthesis of (-)-norbourbonone (29) from (S)-24, which is a novel chiral intermediate. These results are in confliction with some earlier assignmnents of the absolute configuration in the isodaucane group of sesquiterpenes.