動力的に不安定なステレオアイソマーの固体状態誘発制御
Joseph M Keane1, Fei Ding, Michal Sabat
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA.
Journal of the American Chemical Society
|January 22, 2004
まとめ
プロキラルアレンを持つ金属複合体は,溶液中のダイナミックなダイアステロエーマーとして存在しますが,固体状態では単一のダイアステロエーマーとして存在します. この固体状態の選択性は,結合されたアレーンでのステレオ選択的反応を可能にします.
科学分野:
- 有機金属化学 有機金属化学
- ステレオ化学 ステレオ化学
- 固体化学 固体化学
背景:
- TpM (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸) (p-酸)) の形態のアレン複合体は,ヒドリドトリス (p-ピラゾリル) ボレートリガンドと金属中心 (Re,Mo,W) を特徴とする.
- これらの複合体は,パイ酸リガンド (CO,NO) と補助リガンド (1-アルキリミダゾール,ピリジン,PMe3) を含み,プロキラルエタ2-アレンを含んでいます.
- これらの複合体の異なる相における立体化学的振る舞いを理解することは,立体選択反応の設計に極めて重要です.
研究 の 目的:
- TpM (pI-酸) (L) (エタ2-アレン) 複合体の溶液と固体状態のダイアステロエーマー的振る舞いを調査する.
- 固体状態の特性を活用して,結合されたアレン部分の立体選択反応の可能性を探求する.
- プロキラル領域を含む反応のステレオ化学的結果に対する固体相の影響を解明する.
主な方法:
- 異なる金属中心と結合体を持つ様々なアレン複合体の合成.
- 溶液NMRスペクトロスコーピーは,協調ダイアステレオメアの動的均衡を研究する.
- 固体構造とダイアステロエーマー組成を決定するためのX線結晶学.
- 溶液状態と固体状態の両方で結合されたアレンに化学的変換を行う.
主要な成果:
- 複合体は,溶液中の協調ダイアステレオメアの動的均衡として存在します.
- 結晶状および無形固体状態では,単一のダイアステロエーマーのみが観察されます.
- 固体状態の結合領域で実行される反応は,ステレオ選択的に進みます.
- 固体相の同型性は,立体化学的結果を決定する.
結論:
- 固体状態は,アレン複合体の立体化学を制御するためのプラットフォームを提供します.
- ダイアステロエーマー的に純粋な固体相を利用することで,プロキラルアレーンの高度なステレオ選択的機能化が可能になります.
- この研究は,固体状態効果を介して有機金属化学におけるステレオ制御を達成するための戦略を示しています.
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