アルファ,ベータ不飽和アミドのメタロフォスフィット触媒による非対称アシレーション
Mary R Nahm1, Justin R Potnick, Peter S White
1Department of Chemistry, University of North Carolina at Chapel Hill, 27599-3290, USA.
Journal of the American Chemical Society
|February 24, 2006
まとめ
新しいTADDOLフォスフィート触媒は,不飽和アミドに高度にエナチオセレクティブなアシルシルアンの結合添加を可能にします. 結果として得られる製品は,簡単に高エナティオメア過剰に富ませられ,さらなる合成のための貴重な中間物質が得られます.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- アシンメトリック・シンセシス
背景:
- 結合添加反応は,有機合成において根本的なものです.
- エナチオセレクティブ触媒は,キラル分子の生成に不可欠である.
- アシルシランは,炭素-炭素結合形成における多用途の反応剤である.
研究 の 目的:
- アシルシルアネスの結合添加のための高度なエナンチオセレクティブの触媒システムを開発する.
- 開発された触媒システムの範囲と有用性を調査する.
- 反応機構の重要な側面を明らかにする.
主な方法:
- クイラル触媒として,l-メントン由来のTADDOLフォスフィート (6b) の使用.
- N,N-ジメチルアクリルアミド誘導体にp-メトキシベンゾイルサイクロヘキシルジメチルシランのエナチオセレクティブ結合添加.
- 再結晶化による製品の濃縮.
- 脱塩化とバイエル=ヴィリガー酸化によるさらなる変換.
- 機械学的研究のためのX線 difraktionとクロスオーバー実験.
主要な成果:
- TADDOLフォスフィート6bは,高度にエナチオセレクティブの結合添加 (最大99% ee) を触媒化した.
- 製品には,再結晶化時に容易な抗濃縮が加えられました.
- 脱塩化により,正式なステター添加製品が得られ,その後の酸化によりエステル製品が得られた.
- X線 difrractionは,触媒に対する構造的影響を明らかにしました.
- クロスオーバー実験では,シリコンの移動の分子内性質が確認されました.
結論:
- 開発されたTADDOLフォスフィート触媒は,アシルシラネスのエナンチオセレクティブ結合添加に有効です.
- この反応は,その後の変換を通じて,価値あるキラル中間物質へのアクセスを提供します.
- この研究は,分子内シリコン移動を含む,触媒サイクルに関する機械的洞察を提供します.
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