alpha,omega-Bis(2-bromo-4,5-methoxyphenyl)-hexa(4,5-dimethoxy-1,2-phenylene) | 1266122-10-4

• 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: alpha,omega-Bis(2-bromo-4,5-methoxyphenyl)-hexa(4,5-dimethoxy-1,2-phenylene)
• 英文别名: 1-bromo-2-[2-[2-[2-[2-[2-[2-(2-bromo-4,5-dimethoxyphenyl)-4,5-dimethoxyphenyl]-4,5-dimethoxyphenyl]-4,5-dimethoxyphenyl]-4,5-dimethoxyphenyl]-4,5-dimethoxyphenyl]-4,5-dimethoxyphenyl]-4,5-dimethoxybenzene
• CAS: 1266122-10-4
• 化学式: C₆₄H₆₄Br₂O₁₆
• 分子量: 1249.01
• InChiKey: SCDPCXRRSCRIJH-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  14.2
• 重原子数：
  82
• 可旋转键数：
  23
• 环数：
  8.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  148
• 氢给体数：
  0
• 氢受体数：
  16

反应信息

• 作为反应物：
  描述：

  alpha,omega-Bis(2-bromo-4,5-methoxyphenyl)-hexa(4,5-dimethoxy-1,2-phenylene) 在 正丁基锂 、 甲醇 作用下， 以 四氢呋喃 为溶剂， 生成 Octa(4,5-dimethoxy-1,2-phenylene)
  参考文献：
  名称：

  Redox-responsive molecular helices with highly condensed π-clouds

  摘要：

  螺旋结构因其固有的手性结构以及在分离手性化合物或构建分子机器等方面的应用潜力，长期以来一直吸引着化学家的关注。在立体力的作用下，聚合邻苯基形成了紧密的螺旋构象，其中密集的亚苯基单元形成了高度凝聚的 Ï 云。在这里，我们展示了一种发生氧化还原反应动态运动的低聚邻苯。在溶液中，螺旋发生快速反转。然而，在结晶过程中，我们观察到一种手性对称性破坏现象，即每个晶体只包含一种对映体形式。两种手性的晶体都能获得，但都是非对映混合物。此外，在溶液中，螺旋低聚物的动态运动受到单电子氧化的显著抑制。中性和氧化形式的 X 射线晶体学显示，氧化时产生的空穴由重复的邻苯单元共享。这使得螺旋的构象锁定成为可能，并代表了一种持久的自旋记忆。研究表明，苯基低聚物在溶液中可形成左旋和右旋螺旋，但在结晶时会发生手性对称性破坏过程，产生一种非外消旋混合物晶体，每种晶体只含有一种对映体。低聚物的单电子氧化抑制了溶液中镜像螺旋的相互转换，锁定了一种构象，从而产生了手性记忆效应。

  DOI：

  10.1038/nchem.900

文献信息

• Remarkable Effects of Terminal Groups and Solvents on Helical Folding of <i>o</i>-Phenylene Oligomers
  作者：Shinji Ando、Eisuke Ohta、Atsuko Kosaka、Daisuke Hashizume、Hiroyuki Koshino、Takanori Fukushima、Takuzo Aida

  DOI：10.1021/ja303117z

  日期：2012.7.11

  Although o-phenylene oligomers (OPnR) made of dimethoxyphenylene units are thought to be intrinsically dynamic due to pi-electronic repulsion, we show that they fold into a regular helical geometry in CH3CN when they carry terminal groups such as CH3, CH2OH, Br, CO2Bn, and NO2. We evaluated their helical inversion kinetics via optical resolution of long-chain oligomers (e.g. 16- and 24-mers) by chiral HPLC. OP24Br at 298 K shows a half-life for the optical activity of 5.5 h in CH3OH/water (7/3 v/v) and requires 34 h for complete racemization. The perfectly folded helical conformers of OPnR, unlike their imperfectly folded ones, are devoid of extended pi-conjugation and show a cyclic voltammogram featuring reversible multistep oxidation waves.
• <i>o</i>-Phenylene Octamers as Surface Modifiers for Homeotropic Columnar Ordering of Discotic Liquid Crystals
  作者：Takashi Kajitani、Yuki Suna、Atsuko Kosaka、Terutsune Osawa、Shigenori Fujikawa、Masaki Takata、Takanori Fukushima、Takuzo Aida

  DOI：10.1021/ja4087853

  日期：2013.10.2

  Large area homeotropic columnar ordering of pi-conjugated discotic liquid crystals (LCs) is crucial for certain device applications but generally hard to achieve. Here we report polymeric p-phenylene octamer poly-1 and its monomer 1 as the first surface modifiers for homeotropic columnar order of a variety of discotic LCs up to a macroscopic length scale. Their octameric o-phenylene parts are known to fold helically into a cylinder that is reminiscent of a pi-stacked column of discotic LCs. Through-view X-ray diffraction patterns of 1 suggested that this molecule adheres to the glass substrate and directs its cylindrical axis perpendicular to the glass surface. This face on orientation likely nucleates the homeotropic columnar order of discotic LC materials.
• Redox-responsive molecular helices with highly condensed π-clouds
  作者：Eisuke Ohta、Hiroyasu Sato、Shinji Ando、Atsuko Kosaka、Takanori Fukushima、Daisuke Hashizume、Mikio Yamasaki、Kimiko Hasegawa、Azusa Muraoka、Hiroshi Ushiyama、Koichi Yamashita、Takuzo Aida

  DOI：10.1038/nchem.900

  日期：2011.1

  Helices have long attracted the attention of chemists, both for their inherent chiral structure and their potential for applications such as the separation of chiral compounds or the construction of molecular machines. As a result of steric forces, polymeric o-phenylenes adopt a tight helical conformation in which the densely packed phenylene units create a highly condensed π-cloud. Here, we show an oligomeric o-phenylene that undergoes a redox-responsive dynamic motion. In solution, the helices undergo a rapid inversion. During crystallization, however, a chiral symmetry-breaking phenomenon is observed in which each crystal contains only one enantiomeric form. Crystals of both handedness are obtained, but in a non-racemic mixture. Furthermore, in solution, the dynamic motion of the helical oligomer is dramatically suppressed by one-electron oxidation. X-ray crystallography of both the neutral and oxidized forms indicated that a hole, generated upon oxidation, is shared by the repeating o-phenylene units. This enables conformational locking of the helix, and represents a long-lasting chiroptical memory. Phenylene oligomers are shown to form left- and right-handed helices in solution, but a chiral symmetry-breaking process occurs on crystallization to give a non-racemic mixture of crystals that each contains only one enantiomer. One-electron oxidation of the oligomers suppresses the interconversion of the mirror-image helices in solution, locking-in one conformation and leading to chiral memory effects.

  螺旋结构因其固有的手性结构以及在分离手性化合物或构建分子机器等方面的应用潜力，长期以来一直吸引着化学家的关注。在立体力的作用下，聚合邻苯基形成了紧密的螺旋构象，其中密集的亚苯基单元形成了高度凝聚的 Ï 云。在这里，我们展示了一种发生氧化还原反应动态运动的低聚邻苯。在溶液中，螺旋发生快速反转。然而，在结晶过程中，我们观察到一种手性对称性破坏现象，即每个晶体只包含一种对映体形式。两种手性的晶体都能获得，但都是非对映混合物。此外，在溶液中，螺旋低聚物的动态运动受到单电子氧化的显著抑制。中性和氧化形式的 X 射线晶体学显示，氧化时产生的空穴由重复的邻苯单元共享。这使得螺旋的构象锁定成为可能，并代表了一种持久的自旋记忆。研究表明，苯基低聚物在溶液中可形成左旋和右旋螺旋，但在结晶时会发生手性对称性破坏过程，产生一种非外消旋混合物晶体，每种晶体只含有一种对映体。低聚物的单电子氧化抑制了溶液中镜像螺旋的相互转换，锁定了一种构象，从而产生了手性记忆效应。