高スピンコバルト ((II) 複合体によるZ選択性アルケンのイソメリゼーション
Chi Chen1, Thomas R Dugan, William W Brennessel
1Department of Chemistry, University of Rochester , 120 Trustee Road, Rochester, New York 14627, United States.
Journal of the American Chemical Society
|January 7, 2014
まとめ
研究者は,選択的に単純なアルケンをより不安定なZ-同位体へと同位化させるコバルト (II) 触媒を開発した. この画期的な発見は,アルケンの合成におけるステレオ化学を制御するための新しい方法を提供します.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- ステレオセレクティブ合成
背景:
- アルケンのイソメリゼーションは,通常,より安定したE-イソメールを好みます.
- Z-アルケンの選択的合成は,熱力学的好みのために困難です.
研究 の 目的:
- イソメリゼーションによる選択的なZ-アルケンの形成のための触媒システムを開発する.
- コバルト触媒によるアルケンのイソメリゼーションのメカニズムを解明する.
主な方法:
- 使用されたコバルト ((II) 触媒は,大容量のβ-ディケチミネートリガンドを使用しています.
- 反応中介物質を研究するために,同位体ラベリング実験を行いました.
- ステレオ選択性を説明するためのステリックモデルを開発した.
主要な成果:
- 1-アルケンのZ-2-アルケンへの選択的イソメリゼーションを達成しました.
- 静止状態として3座標のコバルト (((II)) アルキル複合体を特定しました.
- シランとエーテルを含む様々な基板で,実証された触媒の有効性.
結論:
- 大量リガンドを持つコバルト (II) 触媒は,Z-アルケンの合成の運動制御を可能にします.
- このメカニズムは,β-ヒドリドの急速な除去と[1,2]-挿入のステップを伴う.
- 移行状態におけるステリック要因は,Z-ステレオ選択性を決定する.
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