皮拉碳基酸盐驱动的代RAFT单次添加
Karen Hakobyan1, Benjamin Noble2, Jiangtao Xu1
1School of Chemical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia. j.xu@unsw.edu.au.
概括
研究可逆激活分裂链转移 (RAFT) 单单元单体插入 (SUMI) 反应中的替代物效应,揭示了Z组和R组相互作用的关键作用. 与传统的RAFT聚合不同,CS键的动态是关键的,重点是C-C键的形成.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 可逆激活碎片化链转移 (RAFT) 聚合是一种强大的技术,用于控制的聚合物合成.
- 单单元单体插入 (SUMI) 提供了对聚合物结构的精确控制,但需要对反应机制有深入的了解.
- 众所周知,替代效应会影响聚合动力学,但它们对RAFT SUMI的具体影响不太清楚.
研究的目的:
- 在代的RAFT SUMI反应中全面研究替代物效应.
- 为了阐明Pyrazole carbodithiolate (PCDT) Z组和R组效应之间的相互作用.
- 将RAFT SUMI的范围扩展到新的单体类型和序列.
主要方法:
- 在RAFT SUMI.I.中使用了pyrazole carbodithiolate (PCDT) 作为Z组.
- 系统地改变R组和单体类型以研究替代物效应.
- 分析了反应动力学和聚合物特性.
主要成果:
- 证明了Z组和R组对RAFT SUMI的影响.
- 确定C-S债券分离/改革是SUMI中的关键步骤,与传统的RAFT不同.
- 成功地将RAFT SUMI扩展到新的单体和序列.
结论:
- 在RAFT SUMI中替代物效应必须在所有反应步骤中进行整体检查.
- 在RAFT SUMI中,C-S债券动态至关重要,与传统RAFT聚合中的C-C债券焦点不同.
- 这项工作为RAFT SUMI提供了更深入的机制理解和更广泛的适用性.
相关概念视频
Radical Formation: Addition
1.7K
Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an...
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an...
1.7K
Conjugate Addition (1,4-Addition) vs Direct Addition (1,2-Addition)
3.2K
α,β-Unsaturated carbonyl compounds with two electrophilic sites, the carbonyl carbon, and the β carbon, are susceptible to nucleophilic attack via two modes: conjugate or 1,4-addition and direct or 1,2-addition.
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are...
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are...
3.2K
Preparation of Alcohols via Addition Reactions
6.2K
Overview
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
6.2K
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
2.2K
Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).
2.2K
Radical Anti-Markovnikov Addition to Alkenes: Overview
3.3K
The addition of hydrogen bromide to alkenes in the presence of hydroperoxides or peroxides proceeds via an anti-Markovnikov pathway and yields alkyl bromides.
3.3K
Conjugate Addition to α,β-Unsaturated Carbonyl Compounds
4.1K
α,β-Unsaturated carbonyl compounds are molecules bearing a carbonyl and alkene functionality in conjugation with each other. The conjugation in the molecule leads to three resonance structures. The hybrid form exhibits two probable electrophilic sites: the carbonyl carbon and the β carbon.
4.1K

![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)
