アントリルで置換されたトライアルキルジジレンは,固有の分子内電荷移転変異を示す
Takeaki Iwamoto1, Maiko Kobayashi, Kei Uchiyama
1Research and Analytical Center for Giant Molecules, Graduate School of Science, Tohoku University, Aoba-ku, Sendai 980-8578, Japan. iwamoto@mail.tains.tohoku.ac.jp
Journal of the American Chemical Society
|February 20, 2009
まとめ
研究者らは,ポリサイクル芳香基を持つ新しい安定ディジレンを合成し,ユニークな分子内電荷伝送相互作用を明らかにした. アントリルで置換されたディジレンには,ディジレンから芳香系への電荷の移転を示す独特の吸収帯が示された.
科学分野:
- オーガノシリコン化学 化学
- フォトケミストリー フォトケミストリー
- 超分子化学とは
背景:
- ディシレンはアルケンのシリコンアナログであり,有機シリコン化学において極めて重要です.
- ポリサイクル芳香炭化水素 (PAH) は,ユニークな電子特性を有しています.
- 充電伝送相互作用を理解することは,新しい機能的材料の設計の鍵です.
研究 の 目的:
- ポリサイクロン芳香置換剤を含む新型ディジレンを合成し,特徴づけること.
- ディジレンとアロマティックパイシステム間の分子内電荷伝送 (ICT) 相互作用を調査する.
- これらの相互作用から生じる光物理学的性質を探求する.
主な方法:
- 1-ナフチル,9フェナントリル,9アントリルで置換されたトライアルキルジジレンの合成.
- 構造と電子特性を確認するために,光譜分析 (UV-Vis,NMR) を行う.
- 電子構造と電荷伝送経路の解明のための計算研究.
主要な成果:
- 単一のポリサイクル芳香置換剤による最初の安定したディジレンの合成が成功しました.
- ディシレンパイとアロマティックパイシステムの間の前例のない分子内電荷伝達の観測.
- アントリルで置換されたディジレンは,ディジレンのPIドナーから芳香PI受容体への電荷移転により,独特のICT吸収帯を示した.
結論:
- 合成されたジセレンは,pi-pi相互作用を研究するための新しいプラットフォームとして機能します.
- 分子内電荷伝達は,これらの化合物の電子的および光学的性質に影響を与える重要な要因です.
- これらの発見は,シリコンベースの新しい材料を設計し,それに合わせた光電子機能を持つための道を開きます.
関連する概念動画
![[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.
02:37Disubstituted Cyclohexanes: cis-trans Isomerism
Depending upon the different spatial orientation of the substituents, the disubstituted cycloalkanes exhibit two types of stereoisomers. The cis isomers have the substituents on the same side of the ring, whereas the trans isomers have the substituents on the opposite sides. These stereoisomers exhibit different physical properties and cannot be interconverted without breaking the carbon-carbon bonds.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
01:29Diels–Alder Reaction: Characteristics of Dienes
The Diels–Alder reaction brings together a diene and a dienophile to form a six-membered ring. Both components have unique characteristics that influence the rate of the reaction.
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is more stable, the...
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is more stable, the...
02:38Electrophilic Addition to Alkynes: Halogenation
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.
02:10Reduction of Alkynes to trans-Alkenes: Sodium in Liquid Ammonia
Alkynes can be reduced to trans-alkenes using sodium or lithium in liquid ammonia. The reaction, known as dissolving metal reduction, proceeds with an anti addition of hydrogen across the carbon–carbon triple bond to form the trans product. Since ammonia exists as a gas (bp = −33°C) at room temperature, the reaction is carried out at low temperatures using a mixture of dry ice (sublimes at −78°C) and acetone.
When dissolved in liquid ammonia, an alkali metal, such as sodium, dissociates into a...
When dissolved in liquid ammonia, an alkali metal, such as sodium, dissociates into a...
01:28Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.