フェロセニル結合ピリリウム塩の対対離子依存のバレンスのタウトメリゼーション
Mio Kondo1, Maai Uchikawa, Kosuke Namiki
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|August 7, 2009
まとめ
新しいフェロセン-アントラキノン化合物におけるバレンスのタウトメリゼーションは,カウンテリオンによって影響を受けます. この研究では,[1-FcPyl]+部分とPF6 (((-) のような対離子間の静電相互作用が,バレンスのタウトメリゼーション (VT) の発生に影響を及ぼすことが明らかになりました.
科学分野:
- マテリアルサイエンス 材料科学
- 無機化学 無機化学とは
- 超分子化学 超分子化学
背景:
- ドナー-受容体 (D-A) 結合化合物は,高度な電子材料にとって極めて重要です.
- フェロセーン (Fc) とアントラキノン (Aq) の分子は,ユニークな電子および酸化還元特性を持っています.
- D-Aシステムの構造-特性関係を理解することは,材料設計の鍵です.
研究 の 目的:
- 新しいフェロセン-エチニラントラキノンの誘導体を合成し,特徴づけること.
- これらの化合物の電子的および構造的性質に対するカウンターイオンの影響を調査する.
- 固体状態のD-Aシステムにおけるバレンスのタウトメリゼーション (VT) の現象を探求する.
主な方法:
- 1-フェロセニルエチニラントラキノン (1-FcAq) とそのサイクルコンデンサ製品,2-フェロセニルオキシオジヒドロディベンゾクロメニリウム塩 ([1-FcPyl]+X-) の合成.
- 電気化学的方法,UV-VIS光譜法,単結晶X線分析,TD-DFT計算を用いた特徴付け.
- 変温モスバウアー光譜法,赤外線光譜法,X線粉末 difraktion (XRPD) でVTと構造変化を研究する.
主要な成果:
- [1-FcPyl]+におけるより大きなpi結合系は,1-FcAq.と比較してLUMOレベルを下げます.
- Fe (II) とFe (III) 種間のバレンスのタウトメリゼーション (VT) は,TFSI () とPF () の塩で観察されたが,BF () の塩では観察されなかった.
- カウンテリオン同一性は,結晶構造内の二面角,平面性,静電相互作用に大きく影響し,VTに影響します.
結論:
- [1-FcPyl]+塩におけるバレンスのタウトメリゼーションの発生は,カウンターアニオンの性質に強く依存しています.
- [1-FcPyl]+部分と対アニオン間の静電相互作用は,Fe (III) 種を安定化または不安定化するのに重要な役割を果たします.
- 二面角や平面性などの構造パラメータはカウンテリオンによって調節され,D-A相互作用やVT行動に影響を与えます.
関連する概念動画
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