関連する実験動画
Updated: May 3, 2026

10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
11.0K
レドックス・スイッチブル・デイジー・チェーン・ロタキサンは,ラジカル-ラジカル相互作用によって誘発される
Carson J Bruns1, Marco Frasconi, Julien Iehl
1Department of Chemistry ‡Department of Materials Science and Engineering §Department of Medicine Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|February 12, 2014
まとめ
研究者らは,ブルーボックスサイクロファンを用いて電気化学的に二酸化可能なデイジーチェーンロタキサンを合成した. これらの分子スイッチは,電気化学的なスイッチングで重要な次元変化を示し,ユニークな機械的反応を提供します.
科学分野:
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
背景:
- 分子機械のための機械的に相互接続された分子 (MIM) の開発.
- 明確な機械的反応を持つ分子スイッチの必要性.
- 既存のビスタブルなカタネンとロタキサンの制限.
研究 の 目的:
- 電気化学的にビスタブルな"ダイジーチェーン"ロタキサンスイッチを合成し,特徴づけること.
- 電気化学的なスイッチングメカニズムを解明するために.
- 機械的運動と分子寸法の変化との関係を調査する.
主な方法:
- ロタキサン前駆体を組み立てるためのクリック化学を用いたワンポット合成.
- 高フィールド (1) H NMRスペクトロスコピーによる特徴付け.
- サイクルボルトメトリーとスペクトロ電気化学を用いた電気化学分析.
主要な成果:
- 周期性および非周期性同位体を持つ6つの異なるダージーチェーン種 (モノマー,ジマー,トリマー) の分離.
- 合成されたロタキサンの詳細な構造的および動的特徴.
- ラジカルカチオン相互作用を含む電気化学的なスイッチングメカニズムの解明.
結論:
- 新型デイジーチェーンロタキサンが電気化学的に制御されたビスタビリティを示しています.
- スイッチングは,分子寸法 (収縮/膨張または収縮/膨張) の有意で明確な変化を誘導します.
- これらの分子は,ユニークな機械的なアクチュエーションを持つ有望な電気化学的にアドレス指定可能な分子スイッチを表しています.
関連する概念動画
Radical Reactivity: Overview
2.2K
Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...
2.2K
Radical Formation: Overview
1.9K
A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the...
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the...
1.9K
Radical Chain-Growth Polymerization: Overview
2.7K
Chain-growth or addition polymerization is successive addition reactions of monomers with a polymer chain. In radical chain-growth polymerization, the reaction proceeds via a free-radical intermediate. The free radical is formed from radical initiators, which spontaneously generate free radicals by homolytic fission. Organic peroxides (such as dibenzoyl peroxide, as shown in Figure 1) or azo compounds are popular radical initiators. A low concentration ratio of radical initiator to monomer is...
2.7K
Radical Formation: Addition
1.6K
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...
1.6K
Radical Reactivity: Nucleophilic Radicals
1.7K
Radicals adjacent to electron-donating groups are called nucleophilic radicals. These radicals readily react with electrophilic alkenes. The SOMO–LUMO interactions are the driving force for the reaction, where the high-energy SOMO of the electron-rich, nucleophilic radicals interacts with the low-energy LUMO of the electron-deficient, electrophilic alkenes. Such SOMO–LUMO interactions are the basis of reactive radical traps, affecting the selectivity in radical reactions. For...
1.7K
Radical Reactivity: Intramolecular vs Intermolecular
1.4K
Radical reactions can occur either intermolecularly or intramolecularly. In an intermolecular radical reaction, a nucleophilic radical adds to an electrophilic alkene or vice versa. In such reactions, the radical and generally the alkene, which is also called the radical trap, are two different molecules. Additionally, for such intermolecular reactions to occur, the radical trap must be active, present in an excess concentration, and the radical starting material must have a weak...
1.4K

![[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)