エナチオセレクティブのイネ-エノンサイクライゼーションのためのキラルカチオンCp (x) Ru (II) コンプレックス
David Kossler1, Nicolai Cramer1
1Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|September 17, 2015
まとめ
チラルのサイクロペンタディエンリルルテニウム (II) 複合体は,イネ-エノンの循環を効率的に触媒化する. この方法は,不飽和エステルまたはウェインレブアミドからアイリド骨格を生成する高いエナチオ選択性を持つピランを素早く生成します.
科学分野:
- 有機金属化学
- キャタリシス
- 有機合成
背景:
- サイクロペンタディエニル (Cp) リガンドは,過渡金属の触媒に不可欠である.
- カチオンのCpRu (II) 複合体は,利用可能な調整部位により,汎用的な触媒用途を提供します.
研究 の 目的:
- キラルCpリガンドを含む新しいCpRu (II) 複合体を合成する.
- 触媒活性を増やすために 可能な調整部位を最大限に活用する.
- yne-enoneサイクルでの効率と選択性を調査する.
主な方法:
- キラルCpリガンドを用いた新しいCp (x) Ru (II) 複合体の合成.
- これらのカチオンの複合体を触媒として利用します
- 正式なヘテロ・ディエルス・アルダー反応 (イネ・エノン・サイクル) を実行する.
主要な成果:
- カチオンのCpRu (II) 複合体は効率的で選択的な触媒である.
- 円循環は急速に進行する (−20°Cで1時間未満).
- ピランは高いエナティオメール比率 (最大99: 1 er) で形成される.
- イリドオイド骨格は,不飽和エステルまたはワインレブアミド基板から直接得られます.
結論:
- チラルCpRu (II) コンプレックスは,原子経済的な変容のための貴重な触媒です.
- 開発された方法は,ピランとイリドオイド骨格への高度なエナンチオセレクティブの経路を提供します.
- この研究は,非対称な触媒におけるCpRu (II) 複合体の有用性を拡大する.
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