设计Tetraoxa[8]circulenes作为主机和传感器
Nino G Petrov1, Patrick Chartier1, Thierry Maris1
1Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3, Canada.
Journal of the American Chemical Society
|December 23, 2021
概括
开发了具有改进合成和独特形表面的新型四氧化[8]. 这些分子作为电子缺乏化合物的敏感传感器,
科学领域:
- 有机化学
- 超分子化学
- 材料科学
背景情况:
- 四氧化具有独特的D4对称结构,具有化和环.
- 这些化合物表现出延伸的平面π-结合和循环基核,但由于合成和溶解性挑战,研究不足.
- 现有的合成方法产生的量很少,而π堆叠限制了它们在同质混合物或共晶体中的应用.
研究的目的:
- 开发改善的四氧化合成方法[8]
- 创建具有形芳香表面的新型,拙形状的四氧化衍生物.
- 探索这些新化合物的结构性质和传感能力.
主要方法:
- 酸诱导的循环凝结反应被优化为四氧化[8]循环烯合成.
- 合成具有大型形电子丰富的芳香表面的衍生物.
- 结晶研究以形成能够包容客人的开放结构.
- 循环甲烯核的结构分析,以调查键长度和结合.
主要成果:
- 开发了增强的合成路径,产生了更多的四氧化[8]循环素.
- 合成的新型衍生物具有显著的形芳香表面.
- 观察到这些化合物结晶成开放的框架,
- 结构分析显示了环氧甲核的变化,与芳香度的变化相关.
结论:
- 使用改进的方法可以更有效地合成tetraoxa[8]circulenes.
- 独特的形结构使客体融入,并有可能形成共晶体.
- 循环八烯核的变化表明适应性和对分子环境的敏感性.
- 这些化合物显示出对缺电子物种,包括芳化合物的敏感传感器的前景.
相关概念视频
01:18Aromatic Hydrocarbon Cations: Structural Overview
3.2K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
Removing one hydrogen from the intervening CH2 group...
3.2K
01:17Thermal Electrocyclic Reactions: Stereochemistry
2.1K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
2.1K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
45.1K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
45.1K
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
2.5K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.5K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.9K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.9K
02:27Predicting Molecular Geometry
36.9K
VSEPR Theory for Determination of Electron Pair Geometries
36.9K