2,6-bis[p-(N,N-dimethylamino)phenyl]-4,8-dibromobenzo[1,2-d;4,5-d']bisoxazole | 1350803-88-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 唑类
• 英文名称: 2,6-bis[p-(N,N-dimethylamino)phenyl]-4,8-dibromobenzo[1,2-d;4,5-d']bisoxazole
• 英文别名: 4-[4,8-dibromo-2-[4-(dimethylamino)phenyl]-[1,3]oxazolo[5,4-f][1,3]benzoxazol-6-yl]-N,N-dimethylaniline
• CAS: 1350803-88-1
• 化学式: C₂₄H₂₀Br₂N₄O₂
• 分子量: 556.256
• InChiKey: QCKMLNSZYFAQKX-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.6
• 重原子数：
  32
• 可旋转键数：
  4
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.17
• 拓扑面积：
  58.5
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为反应物：
  描述：

  4-乙炔基吡啶 、 2,6-bis[p-(N,N-dimethylamino)phenyl]-4,8-dibromobenzo[1,2-d;4,5-d']bisoxazole 在 bis-triphenylphosphine-palladium(II) chloride 、 copper(l) iodide 、 三乙胺 作用下， 以 乙腈 为溶剂， 反应 3.0h， 以32 mg的产率得到4-[2-[4-(dimethylamino)phenyl]-4,8-bis(2-pyridin-4-ylethynyl)-[1,3]oxazolo[5,4-f][1,3]benzoxazol-6-yl]-N,N-dimethylaniline
  参考文献：
  名称：

  Benzobisoxazole Cruciforms: Heterocyclic Fluorophores with Spatially Separated Frontier Molecular Orbitals

  摘要：

  We report the,synthesis of nine conjugated cruciform-shaped molecules based: on the central benzo[1,2-d:4,5-d']bisoxazole nucleus, at Which two conjugated currents intersect at a 90 angle. Cruciforms' substituents were varied pairwise among the electron-neutral phenyl groups, electron-rich 4-(N,N-dimethylamino)phenyl substituents, and electron-poor pyridines. Hybrid density functional theory calculations revealed that the highest occupied molecular orbitals (HOMOs) are localized (24-99%) in all cruciforms, in contrast to the lowest unoccupied molecular orbitals (LUMOs) which are strongly dependent on the substitution and less localized (6-64%). Localization of frontier molecular orbitals (FMOs) along different axes of these cruciforms makes them promising as sensing platforms, since analyte binding to the cruciform should mandate a change in the HOMO-LUMO gap and the resultant. optical properties. This prediction was verified using UV/vis absorption and emission spectroscopy cruciforms' protonation results in hypsochromic and bathochromic shifts consistent with the preferential stabilization of HOMO and LUMO, respectively. In donor-acceptor-substituted systems, a two-step optical response to protonation was observed,wherein an initial bathochromic shifts is followed by a hypsochromic one with continued acidification. X-ray diffraction studies of three selected cruciforms revealed the expected similar to 90 degrees angle between the cruciform's substituents, and crystal packing patterns dominated by [pi...pi] stacking and edge-to-face [C-H center dot center dot center dot pi] contacts.

  DOI：

  10.1021/jo202107w
• 作为产物：
  描述：

  4-二甲氨基苯甲酸 、 3,6-diamino-2,5-dibromo-1,4-hydroquinone 在 磷酸 、 sodium hydroxide 作用下， 以 水 为溶剂， 反应 24.0h， 以90%的产率得到2,6-bis[p-(N,N-dimethylamino)phenyl]-4,8-dibromobenzo[1,2-d;4,5-d']bisoxazole
  参考文献：
  名称：

  Benzobisoxazole Cruciforms: Heterocyclic Fluorophores with Spatially Separated Frontier Molecular Orbitals

  摘要：

  We report the,synthesis of nine conjugated cruciform-shaped molecules based: on the central benzo[1,2-d:4,5-d']bisoxazole nucleus, at Which two conjugated currents intersect at a 90 angle. Cruciforms' substituents were varied pairwise among the electron-neutral phenyl groups, electron-rich 4-(N,N-dimethylamino)phenyl substituents, and electron-poor pyridines. Hybrid density functional theory calculations revealed that the highest occupied molecular orbitals (HOMOs) are localized (24-99%) in all cruciforms, in contrast to the lowest unoccupied molecular orbitals (LUMOs) which are strongly dependent on the substitution and less localized (6-64%). Localization of frontier molecular orbitals (FMOs) along different axes of these cruciforms makes them promising as sensing platforms, since analyte binding to the cruciform should mandate a change in the HOMO-LUMO gap and the resultant. optical properties. This prediction was verified using UV/vis absorption and emission spectroscopy cruciforms' protonation results in hypsochromic and bathochromic shifts consistent with the preferential stabilization of HOMO and LUMO, respectively. In donor-acceptor-substituted systems, a two-step optical response to protonation was observed,wherein an initial bathochromic shifts is followed by a hypsochromic one with continued acidification. X-ray diffraction studies of three selected cruciforms revealed the expected similar to 90 degrees angle between the cruciform's substituents, and crystal packing patterns dominated by [pi...pi] stacking and edge-to-face [C-H center dot center dot center dot pi] contacts.

  DOI：

  10.1021/jo202107w

文献信息

• Critical role of weak [C–H⋯O] hydrogen bonds in the assembly of benzo[1,2-d:4,5-d′]bisoxazole cruciforms into supramolecular sheets
  作者：Jaebum Lim、Karolina Osowska、Jacob A. Armitage、Benjamin R. Martin、Ognjen Š. Miljanić

  DOI：10.1039/c2ce25485a

  日期：——

  This paper explores the structural patterns adopted by a class of eight conjugated cruciforms based on a benzo[1,2-d:4,5-d′]bisoxazole (BBO) nucleus. Within the series, the lengths of cruciforms' x- and y-axes, as well as their terminal substituents, were varied. Two new cruciforms have been prepared using microwave-assisted Sonogashira couplings. Examination of molecular structures of BBO cruciforms revealed the expected cross-shaped geometries, with ∼90° crossing angles between the two conjugation circuits. Most significant deviations from the idealized planar structures were caused by the distortion of benzene rings positioned along the cruciforms' y-axis from the plane of the central benzobisoxazole ring, by as much as 82.1°. Deviations from linearity within carbon–carbon triple bonds were mild, but additively resulted in notably bent y-axes of the two largest examined cruciforms. Most significantly, the packing patterns of benzobisoxazole cruciforms revealed three distinct organizational motifs. Cruciforms with carbonyl groups on either the horizontal or the vertical axis (or both) all organized into two-dimensional infinite sheets, apparently connected chiefly through [C–H⋯O] contacts that varied in length between 2.24 and 2.60 Å, and could be interpreted as weak hydrogen bonds. The parallel layers of these two-dimensional sheets then assembled into three-dimensional structures through [π⋯π] stacking between the layers. The packing patterns of the two cruciforms with 4-(N,N-dimethylamino)phenyl groups on the vertical axis are dominated by one-dimensional columnar or tape-like assemblies that are formed through [π⋯π] stacking; these then organize into two-dimensional sheets, which in turn layer into a three-dimensional structure, but with a ∼60° angle between the adjacent sheets. Finally, in the parent tetraphenyl-substituted cruciform, the sp2 nitrogen on the BBO core plays the key role in the assembly. It establishes 2.64 Å-long [C–H⋯N] contacts with the phenyl groups, mediating the formation of a unique packing pattern in which six tilted columnar assemblies of [π⋯π] stacked cruciforms surround a three-fold rotation axis in the crystal.

  本文探讨了一类基于苯并[1,2-d:4,5-dâ²]双恶唑（BBO）核的八种共轭十字形化合物所采用的结构模式。在该系列中，十字形核的 x 轴和 y 轴长度及其末端取代基均有不同。利用微波辅助的 Sonogashira 耦合技术制备了两种新的十字形核。对 BBO 十字形分子结构的研究显示了预期的十字形几何结构，两个共轭电路之间的交叉角为±90°。与理想化平面结构的最大偏差是由于沿十字形分子 y 轴定位的苯环与中央苯并异噁唑环平面的偏差高达 82.1°。碳碳三键内的线性偏差较小，但加成导致两个最大的受检十字形的 y 轴明显弯曲。最重要的是，苯并异噁唑十字形化合物的堆积模式揭示了三种不同的组织模式。羰基位于水平轴或垂直轴上（或两者都位于水平轴或垂直轴上）的坩埚形均组织成二维无限薄片，显然主要通过[CâHâ¯O]接触连接，接触长度在 2.24 à 和 2.60 à 之间，可解释为弱氢键。然后，这些二维薄片的平行层通过层与层之间的[Ïâ¯Ï]堆积组装成三维结构。纵轴上带有 4-（N,N-二甲基氨基）苯基的两种十字形化合物的堆积模式主要是通过[Ïâ¯Ï]堆积形成的一维柱状或带状集合体；然后这些集合体组织成二维薄片，这些薄片又层叠成三维结构，但相邻薄片之间的夹角为¼60°。最后，在四苯基取代十字形母体中，BBO 核心上的 sp2 氮在组装过程中起着关键作用。它与苯基建立了 2.64 à - 长的[CâHâ¯N]接触，促成了一种独特的堆积模式的形成，在这种模式中，六个倾斜的柱状[Ïâ¯Ï]堆叠十字形集合体围绕着晶体中的三倍旋转轴。
• Selective and Sensitive Fluoride Detection through Alkyne Cruciform Desilylation
  作者：Minyoung Jo、Jaebum Lim、Ognjen Š. Miljanić

  DOI：10.1021/ol401120a

  日期：2013.7.19

  Desilylation of silylethynyl-substituted benzobisoxazole cruciforms can be achieved using stoichiometric amounts of fluoride, leading to a significant change in their UV-vis absorption and fluorescence. This response is observable at micromolar concentrations of fluoride, and, in the case of a triisopropylsilyl-substituted cruciform fluorophore, extraordinarily selective for fluoride over other small inorganic anions, including hydroxide, acetate, and phosphate.
• Benzobisoxazole Cruciforms: Heterocyclic Fluorophores with Spatially Separated Frontier Molecular Orbitals
  作者：Jaebum Lim、Thomas A. Albright、Benjamin R. Martin、Ognjen Š. Miljanić

  DOI：10.1021/jo202107w

  日期：2011.12.16

  We report the,synthesis of nine conjugated cruciform-shaped molecules based: on the central benzo[1,2-d:4,5-d']bisoxazole nucleus, at Which two conjugated currents intersect at a 90 angle. Cruciforms' substituents were varied pairwise among the electron-neutral phenyl groups, electron-rich 4-(N,N-dimethylamino)phenyl substituents, and electron-poor pyridines. Hybrid density functional theory calculations revealed that the highest occupied molecular orbitals (HOMOs) are localized (24-99%) in all cruciforms, in contrast to the lowest unoccupied molecular orbitals (LUMOs) which are strongly dependent on the substitution and less localized (6-64%). Localization of frontier molecular orbitals (FMOs) along different axes of these cruciforms makes them promising as sensing platforms, since analyte binding to the cruciform should mandate a change in the HOMO-LUMO gap and the resultant. optical properties. This prediction was verified using UV/vis absorption and emission spectroscopy cruciforms' protonation results in hypsochromic and bathochromic shifts consistent with the preferential stabilization of HOMO and LUMO, respectively. In donor-acceptor-substituted systems, a two-step optical response to protonation was observed,wherein an initial bathochromic shifts is followed by a hypsochromic one with continued acidification. X-ray diffraction studies of three selected cruciforms revealed the expected similar to 90 degrees angle between the cruciform's substituents, and crystal packing patterns dominated by [pi...pi] stacking and edge-to-face [C-H center dot center dot center dot pi] contacts.