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1,1'-bis (((verdazyl)) フェロセンの二基根で分子内PI二酸化
Bryan D Koivisto1, Andrew S Ichimura, Robert McDonald
1Department of Chemistry, University of Victoria, P.O. Box 3065 STN CSC, Victoria, BC V8W 3V6, Canada.
Journal of the American Chemical Society
|January 19, 2006
まとめ
この研究は,固体状態の安定した緑ジル基の最初のピディメールを提示しています. 溶液では,この構造は失われ,磁気研究は,強力な反鉄磁気結合により,分子が室温で二磁性であることを示しています.
科学分野:
- 有機金属化学 有機金属化学
- ラジカル・ケミストリー (Radical Chemistry) とは
- クリスタログラフィーです.
背景:
- 安定した有機ラジカルは,ユニークな電子および磁気特性を有しています.
- ヴェルダジルラジカルは,安定した有機ラジカルのよく知られているクラスです.
- フェロセンの誘導体は,電子的および構造的多用途性のために広く研究されています.
研究 の 目的:
- 1,1'-bis(verdazyl) フェロセンの固体構造を合成し,特徴づけること.
- この新しい化合物の溶液の行動と磁気特性を調査するために.
- 安定したヴェルダジルラジカルを含む分子内ピディメールの形成を調査する.
主な方法:
- 固体構造を決定するための単結晶X線 difraktion.
- 溶液状態の光譜分析 (NMR,UV-Visなど).
- 磁気感受性測定 (例えば,SQUID磁気測定) を行う.
主要な成果:
- 固体構造は,2つのヴェルダジル基の2つの部分の,前例のない分子内ピディメールを明らかにします.
- ピダイマー配列は溶液に保存されない.
- 磁性特徴は,ラジカル間の強い反鉄磁性結合を示し,室温で二磁性化につながります.
結論:
- 1,1'-bis(VERDAZYL) フェロセンは,固体状態の安定したVERDAZYLラジカルから形成されたパイダイメルの最初の例です.
- 室温で観測された二磁気性は,有意な分子内根幹-根幹相互作用を強調しています.
- この発見は,ラジカル-ラジカル相互作用に基づいて,調節可能な磁気特性を有する分子を設計するための新しい道を開きます.
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