電気染色は,光染色のディチエニルサイクロペンテネスによる
1Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6.
Journal of the American Chemical Society
|March 20, 2003
まとめ
新しい光色および電色化合物が開発されました. これらの1,2-bis(3-チエニル) サイクロペンテンの誘導体は,光または電気化学的酸化を用いて無色と有色の状態を切り替えます.
科学分野:
- マテリアルサイエンス 材料科学
- 有機化学 オーガニック・ケミストリー
- フォトケミストリー フォトケミストリー
背景:
- フォトクロミック素材は,光にさらされると色が変わります.
- エレクトロクロミックな材料は,電気刺激によって色が変わります.
- サイクロペンテンの誘導体は,調節可能な電子特性を提供します.
研究 の 目的:
- 新規の1,2-bis(3-チエニル) シクロペンテンの誘導体を合成し,特徴づけること.
- これらの化合物の光染色および電染色行動を調査するために.
- レスポンシブ素材におけるそれらの潜在的な応用を探求する.
主な方法:
- チオフェンとフェニルの合成は1,2-bis(3-チエニル) サイクロペンテンを置換した.
- UV-Visスペクトロスコーピーは,光色変換をモニタリングします.
- エレクトロクロミック特性を研究するための電気化学的方法.
主要な成果:
- 化合物は,反転性フォトクロミズムを示し,紫外線/可視光で無色 (リング開) 状態と有色 (リング閉) 状態を切り替えます.
- これらの誘導体で前例のない電気色素が観察されました.
- 触媒性酸化により,環閉状態から環開いた状態への変換が可能になります.
結論:
- 研究された1,2-bis(3-チエニル) サイクロペンテンの誘導体は,光色と電色の両方の性質を有しています.
- これらの材料は,光または電気化学的刺激によって調節可能な色の変化を提供します.
- スマートウィンドウ,ディスプレイ,光学データストレージにおける応用の可能性.
関連する概念動画
03:02Colors and Magnetism
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
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01:17Thermal Electrocyclic Reactions: Stereochemistry
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Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
01:26Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
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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.
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Conformation
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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...
01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...