ロジウム触媒による高度なエナチオセレクティブ性があり,1,1-非置換アルケンの直接分子間水酸化により,機能化されていないアルデヒドが生成されます
1Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
Journal of the American Chemical Society
|August 19, 2009
まとめ
新しいロジウム (((I)) 触媒は,アルデヒドによるアクリラミドのエナチオセレクティブ水酸化を可能にします. この反応により,高ステレオ選択性を持つ有価なガンマケトアミドが効率的に生成されます.
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:
- 直接の分子間水酸化は,C-C結合形成の重要な変換である.
- 水酸化酸化のためのエナチオセレクティブ・メソッドの開発は,有機合成における重要な課題です.
研究 の 目的:
- アルファ置換アクリラミドの直接的分子間水酸化のための高度にエナチオセレクティブな触媒系を確立する.
- 高収量と優れたエナティオメリック過剰 (ee) 値を持つガンマケトアミドを合成する.
主な方法:
- キラル・フォスフィン・リガンド ((R,R) -QuinoxP*) を含むカチオンロジウム ((I) 複合体を使用した.
- 結合パートナーとして非機能化されたアリファ酸アルデヒドを使用した.
- 最適な収量とエナチオ選択性のための反応条件を調査した.
主要な成果:
- アルファ置換アクリラミドの高度なエナチオセレクティブの直接分子間水酸化が達成されました.
- 高収量で相応のガンマ・ケトアミドを得ました.
- 優れたエナティオメリック過剰 (ee) 値を示しており,高いステレオコントロールを示しています.
結論:
- 開発されたロジウム (((I) 触媒システムは,非対称な水酸化酸化に有効です.
- この方法により,貴重なキラルガンマケトアミドに効率的にアクセスできます.
- この研究は,エナチオセレクティブ合成におけるキラルロジウム複合体の可能性を強調しています.
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