2-methylenebicyclo<2.2.2>octan-1-ol | 116760-09-9

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 2-methylenebicyclo<2.2.2>octan-1-ol
• 英文别名: 2-methylenbicyclo<2.2.2>octane-1-ol；2-Methylidenebicyclo[2.2.2]octan-1-ol
• CAS: 116760-09-9
• 化学式: C₉H₁₄O
• 分子量: 138.21
• InChiKey: BREBPEIYCJMGDP-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.2
• 重原子数：
  10
• 可旋转键数：
  0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.78
• 拓扑面积：
  20.2
• 氢给体数：
  1
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  三氟乙酸酐 、 2-methylenebicyclo<2.2.2>octan-1-ol 生成 (2-methylidene-1-bicyclo[2.2.2]octanyl) 2,2,2-trifluoroacetate
  参考文献：
  名称：

  TAKEUCHI, KENICHI;AKIYAMA, FUMIO;IKAI, KEIZO;SHIBATA, TADASHI;KATO, MIDOR+, TETRAHEDRON LETT., 29,(1988) N 8, 873-876

  摘要：

  DOI：
• 作为产物：
  描述：

  2-methylenebicyclo<2.2.2>octan-1-ol tert-butyldimethylsilyl ether 在 四丁基氟化铵 作用下， 以 四氢呋喃 为溶剂， 反应 46.0h， 生成 2-methylenebicyclo<2.2.2>octan-1-ol
  参考文献：
  名称：

  Solvolysis of 2-methylene bicyclic bridgehead derivatives: a model for gradual variation of .pi.-conjugation in carbocations

  摘要：

  The rates of solvolysis in ethanol or 80% ethanol at 25-degrees-C have been determined on 2-methylenebicyclo[2.2.2]oct-1-yl triflate (4a), 2-methylenebicyclo[3.2.1]oct-1-yl triflate (5a), 2-methylenebicyclo[3.2.2]non-1-yl mesylate (6a), 2-methylenebicyclo[3.3.1]non-1-yl mesylate (7a-OMs) and heptafluorobutyrate (7a-OHFB), 1-chloro-2-methylenebicyclo[4.2.2]decane (8a), 2-methylenebicyclo[4.3.1]dec-1-yl trifluoroacetate (9a), and 4-methylene-3-homoadamantyl heptafluorobutyrate (10a) and on their corresponding parent 1-bicycloalkyl and 3-homoadamantyl derivatives 4b-10b containing the respective leaving group. The rate ratios for 4a/4b, 5a/5b, 10a/10b, 6a/6b, 7a/7b, 8a/8b, and 9a/9b are 10(-3.9), 10(-1.9), 10(-1.1), 10(0.8), 10(0.9) (for mesylate), 10(-0.2), and 10(0.7), respectively. A plot of the logarithms of the rate ratios against olefinic strain energies of their corresponding unsubstituted bridgehead olefins shows that the smaller the olefinic strain energy, the greater the rate ratio, providing a methodology to gradually change the conjugative ability of bridgehead carbocations. The enhancement of allylic conjugation with increasing skeletal flexibility has been further verified by the enhanced solvolysis rate of (E)-2-ethylidenebicyclo[3.2.2]non-1-yl mesylate ((E)-6e) relative to 6a by a factor of 259. A similar study on much more rigid (E)-2-ethylidenebicyclo[2.2.2]oct-1-yl triflate ((E)-4e) gave a (E)-4e/4a rate ratio of 6.3. AM1 semiempirical molecular orbital calculations on pertinent 2-methylene and (E)-2-ethylidene bridgehead carbocations and corresponding hydrocarbons (L = hydrogen) also supported the increase in the conjugation with increasing skeletal flexibility. The solvolysis products were solely bridgehead substitution products, no indication for the formation of bridgehead olefin via an S(N)1' mechanism having been obtained.

  DOI：

  10.1021/jo00027a050

文献信息

• Evaluation of the π-conjugative effect of the 2-methylene and the 2-oxo substituent on the stability of carbocations in the solvolysis of bicyclic bridgehead derivatives
  作者：Ken'ichi Takeuchi、Fumio Akiyama、Keizo Ikai、Tadashi Shibata、Midori Kato

  DOI：10.1016/s0040-4039(00)82470-3

  日期：1988.1

  The incipient 2-methylenebicyclo[3.2.2]non-1-yl cation is stabilized by allylic conjugation by 4 kcal/mol compared with the more rigid 2-methylenebicyclo[2.2.2]oct-1-yl cation. In contrast to this, no appreciable stabilization due to carbonyl π-conjugation was detected in the 2-oxobicyclo[3.2.2]non-1-yl cation, indicating unimportance of π-conjugative stabilization in tertiary α-keto cations.

  与刚性较强的2-亚甲基双环[2.2.2]辛-1-基阳离子相比，初始的2-亚甲基双环[3.2.2]壬-1-基阳离子通过烯丙基结合稳定在4 kcal / mol。与此相反，在2-氧代双环[3.2.2]壬-1-基阳离子中未检测到由于羰基π-共轭引起的明显稳定，表明在叔α-酮基阳离子中π-共轭稳定的重要性不高。
• TAKEUCHI, KENICHI;AKIYAMA, FUMIO;IKAI, KEIZO;SHIBATA, TADASHI;KATO, MIDOR+, TETRAHEDRON LETT., 29,(1988) N 8, 873-876
  作者：TAKEUCHI, KENICHI、AKIYAMA, FUMIO、IKAI, KEIZO、SHIBATA, TADASHI、KATO, MIDOR+

  DOI：——

  日期：——
• Solvolysis of 2-methylene bicyclic bridgehead derivatives: a model for gradual variation of .pi.-conjugation in carbocations
  作者：Kenichi Takeuchi、Toshikazu Kitagawa、Yasushi Ohga、Masayasu Yoshida、Fumio Akiyama、Akio Tsugeno

  DOI：10.1021/jo00027a050

  日期：1992.1

  The rates of solvolysis in ethanol or 80% ethanol at 25-degrees-C have been determined on 2-methylenebicyclo[2.2.2]oct-1-yl triflate (4a), 2-methylenebicyclo[3.2.1]oct-1-yl triflate (5a), 2-methylenebicyclo[3.2.2]non-1-yl mesylate (6a), 2-methylenebicyclo[3.3.1]non-1-yl mesylate (7a-OMs) and heptafluorobutyrate (7a-OHFB), 1-chloro-2-methylenebicyclo[4.2.2]decane (8a), 2-methylenebicyclo[4.3.1]dec-1-yl trifluoroacetate (9a), and 4-methylene-3-homoadamantyl heptafluorobutyrate (10a) and on their corresponding parent 1-bicycloalkyl and 3-homoadamantyl derivatives 4b-10b containing the respective leaving group. The rate ratios for 4a/4b, 5a/5b, 10a/10b, 6a/6b, 7a/7b, 8a/8b, and 9a/9b are 10(-3.9), 10(-1.9), 10(-1.1), 10(0.8), 10(0.9) (for mesylate), 10(-0.2), and 10(0.7), respectively. A plot of the logarithms of the rate ratios against olefinic strain energies of their corresponding unsubstituted bridgehead olefins shows that the smaller the olefinic strain energy, the greater the rate ratio, providing a methodology to gradually change the conjugative ability of bridgehead carbocations. The enhancement of allylic conjugation with increasing skeletal flexibility has been further verified by the enhanced solvolysis rate of (E)-2-ethylidenebicyclo[3.2.2]non-1-yl mesylate ((E)-6e) relative to 6a by a factor of 259. A similar study on much more rigid (E)-2-ethylidenebicyclo[2.2.2]oct-1-yl triflate ((E)-4e) gave a (E)-4e/4a rate ratio of 6.3. AM1 semiempirical molecular orbital calculations on pertinent 2-methylene and (E)-2-ethylidene bridgehead carbocations and corresponding hydrocarbons (L = hydrogen) also supported the increase in the conjugation with increasing skeletal flexibility. The solvolysis products were solely bridgehead substitution products, no indication for the formation of bridgehead olefin via an S(N)1' mechanism having been obtained.