メチルピリジルピリミジン・リガンドのリング逆転による電子移転を阻害する単一の分子システム
Kuniharu Nomoto1, Shoko Kume, Hiroshi Nishihara
1Department of Chemistry, Graduate school of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|March 4, 2009
まとめ
研究者らは,銅複合体を用いて新しい電子伝送ゲートシステムを開発した. このシステムは,ピリジルピリミジンリガンドの回転運動によって制御され,電子伝送の温度ベースのオン/オフスイッチを可能にします.
科学分野:
- 協調化化学について
- 超分子化学 超分子化学
- 電気化学 電気化学について
背景:
- 電子伝送システムは,分子電子工学にとって極めて重要です.
- 電子の移動を動的に制御することは,この分野の重要な課題です.
- 分子ローターは,反応性ゲーティングメカニズムのための可能性を秘めています.
研究 の 目的:
- 分子回転によって制御される電子伝送ゲートシステムを構築する.
- リガンドダイナミクスとリドックスポテンシャルとの関係を調査する.
- 電子伝送の温度制御されたオン/オフスイッチを実現するために.
主な方法:
- ピリジルピリミジンリガンドによる銅複合体の合成.
- 溶液状態のNMRスペクトロスコピーを用いたダイナミックなプロセス調査.
- レドックスポテンシャルシフトを決定するための電気化学測定.
主要な成果:
- 回転動的リガンドを持つ銅複合体 (1.BF(4) が成功して合成されました.
- ピリジルピリミジンリガンドは,293 Kで73 kJ mol ((-1) のバリアを持つ同位体相互変換を示した.
- 温度によって引き起こされたリガンド構成の変化は,銅中心の酸化還元電位を−0.14Vにシフトさせ,電子伝送を遮断しました.
結論:
- この研究は,分子回転によって制御される機能的な電子転送ゲートを実証しています.
- 温度は,ゲーティングの行動を調節する効果的な外部刺激として機能します.
- この研究は,応答性分子電子デバイスの設計のための基礎を提供します.
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関連する概念動画
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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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01:17Thermal Electrocyclic Reactions: Stereochemistry
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Selection Rules: Thermal Activation
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02:51Metal-Ligand Bonds
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02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
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CFT focuses on...
03:02Colors and Magnetism
Color in Coordination Complexes
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