(E)-1-(2,2-dimethylcyclopentylidene)-1,2-diphenyl-2-ethanol | 128037-85-4

• 分子结构分类: 有机化合物 - 苯丙烷和聚酮 - 直链 1,3-二芳基丙烷
• 英文名称: (E)-1-(2,2-dimethylcyclopentylidene)-1,2-diphenyl-2-ethanol
• 英文别名: (2E)-2-(2,2-dimethylcyclopentylidene)-1,2-diphenylethanol
• CAS: 128037-85-4
• 化学式: C₂₁H₂₄O
• 分子量: 292.421
• InChiKey: OSMOLCQHQMPELZ-VHEBQXMUSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.5
• 重原子数：
  22
• 可旋转键数：
  3
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.33
• 拓扑面积：
  20.2
• 氢给体数：
  1
• 氢受体数：
  1

反应信息

• 作为产物：
  描述：

  6-bromo-3,3-dimethyl-1-phenyl-1-hexyne 在 叔丁基锂 、 sodium iodide 作用下， 以 丙酮 为溶剂， 反应 4.0h， 生成 (E)-1-(2,2-dimethylcyclopentylidene)-1,2-diphenyl-2-ethanol
  参考文献：
  名称：

  Cyclization of acetylenic alkyllithiums

  摘要：

  The scope and limitations of cyclization reactions involving acetylenic alkyllithiums, which were prepared at -78-degrees-C by lithium-iodine exchange between the corresponding iodide and tert-butyllithium in a solution of n-pentane-diethyl ether (3:2 by volume), have been investigated. 4-Pentynyllithiums, 5-hexynyllithiums, and 6-heptynyllithiums bearing a phenyl or trimethylsilyl substituent on the triple bond undergo regiospecific exo-dig cyclization to give 4-, 5-, and 6-membered rings, respectively, bearing an exocyclic lithiomethylene moiety. Cyclization of the analogous alkyl-substituted acetylenic alkyllithiums seems to be confined to the 5-exo mode. The vinyllithium products of the cyclizations may be trapped by reaction with electrophiles to afford functionalized cycloalkylidene derivatives in good yield. The cyclization reactions were found to be highly stereoselective: intramolecular addition of the C-Li unit to the triple bond to produce 4- or 5-membered rings proceeds in a syn fashion to generate isomerically pure exocyclic vinyllithiums that may be functionalized to give stereoisomerically pure products. At the higher temperatures needed to effect cyclization of 6-heptynyllithiums, the initially formed (Z)-vinyllithium intermediate is isomerized to the more stable E-isomer which, when trapped with an electrophile, affords stereoisomerically pure product formally derived from anti addition to the triple bond.

  DOI：

  10.1021/ja00061a006

文献信息

• Intramolecular addition of alkyllithiums to acetylenes: Regiospecific 4-, 5-, and 6-exo-dig cyclizations
  作者：William F. Bailey、Timo V. Ovaska

  DOI：10.1016/s0040-4039(00)94585-4

  日期：1990.1

  Primary acetylenic alkyllithiums bearing a phenyl substituent on the triple bond, which may be prepared in virtually quantitative yield by low-temperature lithium-iodine interchange, undergo regiospecific exo-dig cyclization via stereoselective syn-addition of CH2Li to the carbon-carbon triple bond to give four-, five-, and six-membered carbocycles bearing an easily functionalized exocyclic lithiomethylidene

  可以通过低温锂-碘交换以几乎定量的方式制备在三键上带有苯基取代基的炔基烷基锂，并通过将CH 2 Li立体选择性合加成到碳-碳三元基团上进行区域特异性的ex-dig环化反应结合形成具有容易官能化的环外硫代亚甲基部分的四元，五元和六元碳环。类似的烷基取代的炔基烷基锂的环化限于5 -exo-dig模式。