C1-4 基化烯化物与轻基,通过金属光催化在流动中启用
Antonio Pulcinella1, Prakash Chandra Tiwari1, Alberto Luridiana1,2
1Flow Chemistry Group, Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.
Angewandte Chemie (International ed. in English)
|August 28, 2024
概括
这项研究引入了一种在室温下将气态基与基基合的新方法,使复杂有机分子的合成成为可能. 这一突破利用光催化和催化,为制药和农业化学开发提供了实用的方法.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 摄影化学的使用.
背景情况:
- 气态C1-4基是基碎片的丰富来源,但由于具有挑战性的C-H键裂变,它们很少用于合成.
- 形成C(sp2) -C(sp3) 键对于制造药品和农业化学品至关重要.
- 现有的方法需要高温和高压,这限制了它们的应用.
研究的目的:
- 开发一种将气态基与 (异质) 基化物合的方法.
- 在温和条件下 (室温) 实现这种合.
- 为了使复杂的有机分子,包括药品和农业化学品的合成.
主要方法:
- 原子转移 (HAT) 光催化和催化交叉合的组合.
- 利用流量技术,减少反应时间和可扩展性.
- 运用密度函数理论 (DFT) 计算来理解反应机制.
主要成果:
- 在室温下成功实现了气态基和 (异质) 烯化物之间的合.
- 流技术可以缩短反应时间和可扩展的合成.
- 在DFT计算中,氧化添加被确定为速度决定的步骤,受基数大小的影响.
- 在和butan中观察到基性异构,与甲烯的电子性质有关.
结论:
- 介绍了一种新的,实用的,可扩展的方法,用于使用丰富的气态烯形成C(sp2) -C(sp3键.
- 开发的方法适合在学术界和工业界广泛采用,用于合成复杂的有机分子.
- 强调氧化添加和电子性质在控制反应选择性和效率方面的关键作用.
相关概念视频
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.7K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
7.7K
Electrophilic Addition to Alkynes: Halogenation
8.2K
Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
8.2K
Preparation of Alkynes: Alkylation Reaction
10.0K
Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
10.0K
Halogenation of Alkenes
15.4K
Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
15.4K
Radical Substitution: Allylic Bromination
5.0K
In organic synthesis, the formation of products can be altered by changing the reaction conditions. For example, a dibromo addition product is formed when propene is treated with bromine at room temperature. In contrast, propene undergoes allylic substitution in non-polar solvents at high temperatures to give 3-bromopropene. In order to avoid the addition reaction, the bromine concentration must be kept as low as possible throughout the reaction. This can be achieved using N-bromosuccinimide...
5.0K
Electrophilic Aromatic Substitution: Friedel–Crafts Alkylation of Benzene
6.5K
Friedel–Crafts reactions were developed in 1877 by the French chemist Charles Friedel and the American chemist James Crafts. Friedel–Crafts alkylation refers to the replacement of an aromatic proton with an alkyl group via electrophilic aromatic substitution. A Lewis acid catalyst such as aluminum chloride reacts with an alkyl halide to form a carbocation. The resulting carbocation then reacts with the aromatic ring and undergoes a series of electron rearrangements before giving the...
6.5K
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)

