1-Methyl-2-penta-1,4-dien-2-ylbenzene | 134261-82-8

• 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: 1-Methyl-2-penta-1,4-dien-2-ylbenzene
• CAS: 134261-82-8
• 化学式: C₁₂H₁₄
• 分子量: 158.243
• InChiKey: YVRQCBUJZURDCF-UHFFFAOYSA-N

物化性质

• 沸点：
  225.5±20.0 °C(Predicted)
• 密度：
  0.880±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  4.4
• 重原子数：
  12
• 可旋转键数：
  3
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.17
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为产物：
  描述：

  2-[(trimethylsilyl)methyl]benzyl alcohol 在 正丁基锂 、 四丁基氟化铵 、 三溴化磷 、 富马酸二甲酯 作用下， 以 乙醚 、 乙腈 为溶剂， 反应 8.33h， 生成 1-Methyl-2-penta-1,4-dien-2-ylbenzene
  参考文献：
  名称：

  Synthesis and Conversions of Substituted o-[(Trimethylsilyl)methyl]benzyl p-Tolyl Sulfones to o-Quinodimethanes and Products Thereof

  摘要：

  Use of o-[(trimethylsilyl)methyl]benzyl p-tolyl sulfone (3) for synthesis and cycloaddition of substituted o-quinodimethanes has been investigated. Sulfone 3 is prepared from 2-methylbenzyl alcohol (4) by reactions with n-BuLi and chlorotrimethylsilane to form o-[(trimethylsilyl)methyl]benzyl alcohol (7) which phosphorus tribromide converts to o-[(trimethylsilyl)methyl]benzyl bromide (8). Displacement of 8 with sodium p-toluenesulfinate yields 3. Sulfone 3 is alkylated at its alpha-sulfonyl position upon deprotonation with n-BuLi followed by methyl iodide, ethyl, butyl, allyl, and benzyl bromides, and 5-bromo-1-pentene, respectively. Acylations occur using acid chlorides. Dialkylation occurs upon further reaction with n-BuLi and an alkyl halide. 1,4-Eliminations of alpha,alpha-dialkyl sulfones 11 with tetrabutylammonium fluoride (TBAF) give alpha,alpha-dialkyl-o-quinodimethanes (29); 3 is therefore a synthon for the o-quinadimethane-alpha,alpha-dianion (34). o-Quinodimethanes 29 undergo (1) cycloaddition with acrylonitrile, acrylate esters, and alkyl fumarates to yield 1,1-disubstituted-tetrahydronaphthalenes (30) and (2) 1,5-sigmatropic rearrangements of hydrogen to give styrenes (32). The stereochemistries of the various cycloadditions reveal significant mechanism information.

  DOI：

  10.1021/jo970592c

文献信息

• Nickel-catalyzed olefination of cyclic benzylic dithioacetals by Grignard reagents. Scope and mechanism
  作者：Zhi Jie Ni、Nai Wen Mei、Xian Shi、Yih Ling Tzeng、Maw Cherng Wang、Tien Yau Luh

  DOI：10.1021/jo00012a043

  日期：1991.6

  The details of the first nickel-catalyzed olefination of cyclic dithioacetals to form substituted styrenes and aryl-substituted 1,4-pentadienes are described. The reaction represents a new synthetic use of the dithioacetal functionality. Only nickel complexes catalyzed these cross-coupling reactions; palladium complexes displayed no catalytic activity under the reaction conditions employed. Selective coupling occurred. A mechanism for the reaction is proposed. The experimental evidence indicates that, in these nickel-catalyzed couplings, cyclic dithioacetals are more reactive than their acyclic analogues. This increased reactivity appears to be the result of maintaining the two sulfur atoms in close proximity to each other by the use of a short chain of methylene groups.
• Synthesis and Conversions of Substituted <i>o</i>-[(Trimethylsilyl)methyl]benzyl <i>p</i>-Tolyl Sulfones to <i>o</i>-Quinodimethanes and Products Thereof
  作者：Brian D. Lenihan、Harold Shechter

  DOI：10.1021/jo970592c

  日期：1998.4.1

  Use of o-[(trimethylsilyl)methyl]benzyl p-tolyl sulfone (3) for synthesis and cycloaddition of substituted o-quinodimethanes has been investigated. Sulfone 3 is prepared from 2-methylbenzyl alcohol (4) by reactions with n-BuLi and chlorotrimethylsilane to form o-[(trimethylsilyl)methyl]benzyl alcohol (7) which phosphorus tribromide converts to o-[(trimethylsilyl)methyl]benzyl bromide (8). Displacement of 8 with sodium p-toluenesulfinate yields 3. Sulfone 3 is alkylated at its alpha-sulfonyl position upon deprotonation with n-BuLi followed by methyl iodide, ethyl, butyl, allyl, and benzyl bromides, and 5-bromo-1-pentene, respectively. Acylations occur using acid chlorides. Dialkylation occurs upon further reaction with n-BuLi and an alkyl halide. 1,4-Eliminations of alpha,alpha-dialkyl sulfones 11 with tetrabutylammonium fluoride (TBAF) give alpha,alpha-dialkyl-o-quinodimethanes (29); 3 is therefore a synthon for the o-quinadimethane-alpha,alpha-dianion (34). o-Quinodimethanes 29 undergo (1) cycloaddition with acrylonitrile, acrylate esters, and alkyl fumarates to yield 1,1-disubstituted-tetrahydronaphthalenes (30) and (2) 1,5-sigmatropic rearrangements of hydrogen to give styrenes (32). The stereochemistries of the various cycloadditions reveal significant mechanism information.