活性化されていない二次カルボキシアミドのAl(III) 触媒によるトランスアミデーションのメカニズム
Justin M Hoerter1, Karin M Otte, Samuel H Gellman
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|April 13, 2006
まとめ
新しいアルミニウム (((III)) 触媒は,アミンと反応しないカルボキシアミドの効率的なトランスアミデーションを可能にします. この発見は,穏やかな条件下でアミド結合形成のための新しい経路を提供し,典型的な反応性の課題を克服します.
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
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- 二次カルボキシアミドには,一般的に反応しない炭素-窒素結合があります.
- トランスアミド化反応は,アミドを含む分子を合成するために極めて重要です.
研究 の 目的:
- トライサミドアルミニウム (Trisamidoaluminum) (((III) ダイマーの催化トランスアミデーション反応のメカニズムを解明する.
- アルミニウム (III) 触媒がカルボキシアミドとアミンをどのように活性化するかを理解する.
主な方法:
- 反応速度の法則を定めるための運動学的研究.
- NMR (1H, 13C) とFTIRを含むスペクトル解析.
- デュテラートアミン基板を用いた運動同位体効果の研究.
主要な成果:
- 触媒反応は二分子速度の法則に従っており,アルミニウム (III) とアミンの濃度では第一位である.
- 顕微鏡のデータによると,トリス - カッパ - 2 - アミデート - アルミニウム - III 複合体を含む触媒の静止状態を示している.
- 有意な動的同位体効果は,アミンの調整と陽子の移転が速度制限のステップに先行することを示唆しています.
結論:
- このメカニズムは,前均衡のアミン調整と,触媒への陽子の移転を含む.
- 速度を制限する分子内アミデーションが発生し,アルミニウム (III) によるカルボキシアミドの活性化が促進されます.
- アルミニウム (((III) 触媒は,核愛者と電愛者の双機能活性化を示す.
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