6-[5-[[2-(6-Carboxylatopyridin-2-yl)-1-ethylbenzimidazol-5-yl]methyl]-1-ethylbenzimidazol-2-yl]pyridine-2-carboxylate | 725266-27-3

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 苯并咪唑类
• 英文名称: 6-[5-[[2-(6-Carboxylatopyridin-2-yl)-1-ethylbenzimidazol-5-yl]methyl]-1-ethylbenzimidazol-2-yl]pyridine-2-carboxylate
• CAS: 725266-27-3
• 化学式: C₃₁H₂₄N₆O₄
• 分子量: 544.569
• InChiKey: XERBCJFQRBGDIV-UHFFFAOYSA-L

计算性质

• 辛醇/水分配系数(LogP)：
  5.8
• 重原子数：
  41
• 可旋转键数：
  6
• 环数：
  6.0
• sp3杂化的碳原子比例：
  0.16
• 拓扑面积：
  142
• 氢给体数：
  0
• 氢受体数：
  8

反应信息

• 作为反应物：
  描述：

  europium(III) perchlorate hydrate 、 6-[5-[[2-(6-Carboxylatopyridin-2-yl)-1-ethylbenzimidazol-5-yl]methyl]-1-ethylbenzimidazol-2-yl]pyridine-2-carboxylate 以 重水 为溶剂， 生成
  参考文献：
  名称：

  Lanthanide Helicates Self-Assembled in Water:  A New Class of Highly Stable and Luminescent Dimetallic Carboxylates

  摘要：

  The segmental ligand bis{1-ethyl-2-[6'-carboxy)pyridin-2'-yl]benzimidazol-5-yl}methane (L-C) reacts with the entire series of Ln(III) ions to yield a new class of neutral lanthanide carboxylates, the triple-stranded dimetallic helicates [Ln(2)(L-C-2H)(3)], which are stable in water in the pH range 4-13. A competitive titration with 1,4,7,10-tetraazacyclododecane-N,N',N",N'''-tetraacetic acid (dota) shows the Eu-III helicate to have a stability comparable to that of [Eu(dota)](-). According to the X-ray structures of isotypical [Ln(2)(L-C-2H)(3)].20.5H(2)O (Ln = Eu, Tb) (C(93)H(72)Ln(2)N(18)O(12).20.5H(2)O, monoclinic, P2(1)/c, Z = 8), the helicates are comprised of two types of slightly different molecules (A, B) within the asymmetric unit. The three ligand strands are helically wrapped around the two nine-coordinate Ln(III) ions, leading to pseudo-D-3 symmetries around the metals. The Ln(III) distances lie in the ranges 8.81--8.83 Angstrom for molecules A and 9.04-9.07 Angstrom for molecules B, while the helical pitch amounts to 23.7--23.8 Angstrom (A) and 24.5-24.7 Angstrom (B). In solution, the helicates retain time-averaged D-3 symmetries along the entire Ln(III) series, as shown by H-1 and C-13 NMR. The derivation of equations adapted to heterodimetallic complexes allows the separation of contact and dipolar contributions to the isotropic paramagnetic shift. Somewhat different structures are evidenced between larger (Ln = Ce-Tb) and smaller (Ln = Er--Yb) Ln(III) ions, attributed to a lengthening of the helix on going toward heavier lanthanides. The photophysical properties of the helicates depend on the nature of the Ln(III) ion, and LC is revealed to be a good sensitizer of Eu-III. The flexible route used to synthesize LC opens interesting perspectives for the fine-tuning of the chemical and photophysical properties of lanthanide-containing homodimetallic helicates with potential applications in labeling and sensing technologies.

  DOI：

  10.1021/ja991854q