基于环氧化物和亚齐里丁的最近进展 [3+2] 取消
1School of Chemical and Pharmaceutical Engineering, Changzhou Vocational Institute of Engineering, Gehu Road 33, Wujin District, Changzhou, 213164, P. R. China.
Chemistry, an Asian journal
|February 18, 2025
概括
环氧化物和亚齐里丁是通过 [3+2] 无效反应合成五个成员的异极循环的新型1,3双极等价物. 本综述涵盖了以环氧化物和亚齐里丁为基础的注销的最新进展,重点关注各种催化环开放条件.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 异环化学 异环化学
背景情况:
- [3+2] 无效反应是合成五个成员的异环化合物的关键.
- 传统的方法通常使用O中心和N中心的化物.
- 环氧化物和亚齐里丁在这些反应中为1,3-二极体提供了替代合成等价物.
研究的目的:
- 审查使用环氧化物和亚齐里丁的 [3+2] 无效反应的最新进展.
- 根据它们的环开放机制和催化条件来对这些反应进行分类.
- 要突出环氧化物和亚齐里丁在构建功能化异环环的实用性.
主要方法:
- 关于以环氧化物和亚齐里丁为基础的 [3+2] 取消的最新文献的综述.
- 根据环开放条件对反应进行分类:酸催化,有机催化和过渡金属催化.
- 反应途径的分析,包括协调和正式的循环添加.
主要成果:
- 环氧化物和亚齐里丁有效地参与与各种双极性动物的 [3+2] 无效.
- 不同的催化系统 (酸/,有机催化,过渡金属) 能够控制环开放和无效.
- 这些方法提供了功能化的四二 furan,pyrrolidines和相关的异环结构的访问.
结论:
- 基于环氧化物和亚齐里丁的 [3+2] 取消是异环合成的多功能策略.
- 催化在控制这些转变的反应性和选择性方面发挥着至关重要的作用.
- 这些方法扩大了合成工具包,以获取有价值的五个成员的异环.
相关概念视频
03:00Preparation of Epoxides
Overview
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
02:24Acid-Catalyzed Ring-Opening of Epoxides
Epoxides that are three-membered ring systems are more reactive than other cyclic and acyclic ethers. The high reactivity of epoxides originates from the strain present in the ring. This ring strain acts as a driving force for epoxides to undergo ring-opening reactions either with halogen acids or weak nucleophiles in the presence of mild acid. The acid catalyst converts the epoxide oxygen, a poor leaving group, into an oxonium ion, a better leaving group, making the reaction feasible. The...
02:26Base-Catalyzed Ring-Opening of Epoxides
Due to their highly strained structures, epoxides can readily undergo ring-opening reactions through nucleophilic substitution, either in the presence of an acid or a base. The nucleophilic substitution reactions in the presence of acid are called acid-catalyzed ring-opening reactions, and nucleophilic substitution reactions in the presence of a base are called base-catalyzed ring-opening reactions. Epoxides undergo base-catalyzed ring-opening reactions in the presence of a strong nucleophile...
01:16Cycloaddition Reactions: Overview
Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
![[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2Ffiles%2Fmedia%2Fscience-education%2Fscience-education-thumbs%2F12417.jpg&w=3840&q=75)
01:16[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
01:27Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
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