旋持久的超稳定
Wenqi Liu1, Chenjian Lin1, Jacob A Weber1
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|April 4, 2020
概括
这项研究详细介绍了氨酸在旋受体中的封装,实现了高结合亲和度,并显著提高了它们的光学特性和化学稳定性,用于先进材料应用.
科学领域:
- 超分子化学
- 材料科学
- 摄影化学
背景情况:
- 氨酸是重要的染色体,在催化和光疗中具有应用.
- 在水性介质中控制氨酸的聚合和稳定性仍然是一个挑战.
研究的目的:
- 开发一种用于封装在水中的氨酸的环氧受体.
- 研究封装对的光物理性质和化学稳定性的影响.
主要方法:
- 一个三环旋受体的合成.
- 用水中的受体结合自由基和的研究.
- 封装氨酸的光谱分析 (吸收,排放)
- 在恶劣条件下的化学稳定性评估 (酸性,D/H交换).
主要成果:
- 在水中封装氨酸时获得的亚纳米结合亲和度.
- 由于受体的三环结构,发现了两个同构异构体.
- 显著增强光量子产量和红移光学特性.
- 没有前例的化学稳定性, 阻断D/H交换, 质子化, 和溶解.
结论:
- 三环旋有效封装氨酸,调节它们的特性.
- 封装可以改善光物理特性和特殊的化学惰性.
- 在先进材料,人工光合作用和生物医学设备的潜在应用.
相关概念视频
Thermal and Photochemical Electrocyclic Reactions: Overview
2.8K
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.
2.8K
Aromatic Hydrocarbon Cations: Structural Overview
3.6K
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...
3.6K
Photochemical Electrocyclic Reactions: Stereochemistry
2.1K
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
2.1K
Stability of Substituted Cyclohexanes
14.5K
This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
14.5K
Woodward–Hoffmann Selection Rules and Microscopic Reversibility
3.7K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
3.7K
Pericyclic Reactions: Introduction
9.5K
Pericyclic reactions are organic reactions that occur via a concerted mechanism without generating any intermediates. The reactions proceed through the movement of electrons in a closed loop to form a cyclic transition state, where rearrangement of the σ and π bonds yields specific products.
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic...
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic...
9.5K
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)

