相关实验视频
Updated: Sep 10, 2025
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
05:15
Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
6.9K
七个成员环的远程功能化迁移组策略
Wenlai Han1, Taehwan Hwang1,2, Christina Lian1
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|August 19, 2025
概括
研究人员开发了一种新的光催化方法来合成复杂的七个环. 这一策略使循环的直接功能化成为可能,为有价值的生物活性化合物提供更有效的途径.
科学领域:
- 有机化学
- 合成方法
- 光催化
背景情况:
- 七个环在生物活性分子中至关重要,
- 传统的方法通常需要复杂的环组装或预先功能化的构建块.
- 更简单的循环前体的直接功能化是一种有吸引力的合成替代品.
研究的目的:
- 开发一种新的光催化技术,用于合成替代的七个环.
- 能够直接使用可用的循环前体.
- 解决目前用于中型环的合成方法的局限性.
主要方法:
- 使用脱和硫醇催化剂进行光催化过环基迁移.
- 在温和条件下使用发光二极管 (LED) 照射.
- 采用动态运动方法,涉及可逆原子转移和基质介导迁移.
主要成果:
- 转化1,1-非替代的乙环甲成1,4-非替代的产品.
- 在七个成员环内展示选择性C-H功能.
- 区域选择性访问密集替代的七个环系统.
结论:
- 开发的光催化方法提供了一个高效的区域选择性途径,以替代七个环.
- 这一策略克服了与中型环的传统合成相关的挑战.
- 这种方法为在药物化学和材料科学中访问复杂的分子结构提供了有价值的新工具.
相关概念视频
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
6.3K
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
6.3K
Nucleophilic Aromatic Substitution: Addition–Elimination (SNAr)
4.0K
Nucleophilic substitution in aromatic compounds is feasible in substrates bearing strong electron-withdrawing substituents positioned ortho or para to the leaving group. The reaction proceeds via two steps: the addition of the nucleophile and the elimination of the leaving group.
The reaction begins with an attack of the nucleophile on the carbon that holds the leaving group. This results in the delocalization of the π electrons over the ring carbons. The resonance interaction between...
The reaction begins with an attack of the nucleophile on the carbon that holds the leaving group. This results in the delocalization of the π electrons over the ring carbons. The resonance interaction between...
4.0K
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
2.0K
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
2.0K
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
2.8K
The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.
2.8K
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
4.8K
Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.
4.8K
Stability of Substituted Cyclohexanes
13.0K
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...
13.0K

