キラルビス (イミダゾリジン) ピリジン-Cu (OTf) 2:イミノエステルとニトロアルケンのサイクロアディションによる触媒的非対称性のあるエンドセレクティブ [3 + 2] サイクル
Takayoshi Arai1, Asami Mishiro, Naota Yokoyama
1Department of Chemistry, Graduate School of Science, Chiba University, Inage, Chiba 263-8522, Japan. tarai@faculty.chiba-u.jp
Journal of the American Chemical Society
|March 30, 2010
まとめ
非対称な合成のために新しいキラル触媒であるPyBidine-Cu (((OTf) (((2) が開発されました. この触媒は,高度なエンドセレクティブ反応を効率的に促進し,99%までのエナティオメール過量を持つ製品を生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・カタリシス
背景:
- 新規のキラルリガンドの開発は,非対称合成を進めるために極めて重要です.
- C(2) -対称リガンドは,触媒反応においてユニークなステレオ化学的制御を提供します.
研究 の 目的:
- 新しいC(2) -対称ビス(イミダゾリジン) ピリジン (PyBidine) リガンドを合成し,特徴づけること.
- 非対称反応におけるPyBidine-Cu ((OTf) ((2) 複合体の触媒活性を評価する.
主な方法:
- PyBidine リガンド合成のための単一の凝縮反応.
- PyBidine-Cu ((OTf) ((2) コンプレックス) の形成.
- イミノエステルとニトロアルケンの触媒的非対称反応.
主要な成果:
- PyBidine リガンドが成功して合成されました.
- PyBidine-Cu ((OTf) ((2) 複合体は,高い触媒活性を示した.
- 高度にエンドセレクティブなアドゥクトは,99%までのエナティオメール過量 (ee) を得られた.
結論:
- 新しいPyBidineリガンドとその銅複合体は,非対称合成のための効果的な触媒です.
- PyBidineリガンドの"キラルフェンス"メカニズムは,高いステレオ選択性に寄与する.
- この触媒系は,エナティオメリックに濃縮された化合物への有望な経路を提供します.
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