高度にエナチオセレクティブの銅 (((I) -フェスルフォスがアゾメチンイリドの1,3-二極サイクロアディションを触媒化した
Silvia Cabrera1, Ramón Gómez Arrayás, Juan C Carretero
1Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Journal of the American Chemical Society
|November 25, 2005
まとめ
新しいキラルルイス酸触媒は,非対称な1,3-二極サイクロアディション反応を効率的に駆動します. このシステムは,ケチミン由来基板であっても,アゾメチンイリドの高収量と例外的なエナチオ選択性を達成します.
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:
- アゾメチンイリドは,有機合成で使用される多用途の1,3-二極体です.
- 触媒的非対称性1,3-二極性サイクロアディションは,キラル分子を作る上で極めて重要です.
- これらの反応のための効率的で選択的な触媒の開発は,依然として重要な課題です.
研究 の 目的:
- 非対称1,3-二極サイクロアディション反応のための高効率のキラルルイス酸触媒を開発する.
- この触媒システムの範囲と限界を様々なアゾメチンと二極性基板で調査する.
- ケチミン由来アゾメチンを用いた最初の成功した触媒的非対称サイクロアディションを報告する.
主な方法:
- Cu ((CH3CN) 4ClO4と平面キラルP,S-リガンドフェスルフォスを用いて触媒システムの形成.
- アゾメチンイリドの1,3-二極サイクロアディションにおける触媒の適用.
- 反応産物の収量,ダイアステレオ選択性 (エンドアダクト),およびエナチオ選択性 (ee%) の分析.
主要な成果:
- Cu(I) -フェスルフォス触媒システムは,キラルルイス酸として高い効率を示した.
- 低触媒負荷 (0.5-3モル%) が有効で,良い収量でエンドアダクトを生成しました.
- >99% eeまでの例外的なエナチオセレクティブが達成されました.
- この手順は,アゾメチンと二極性コンポーネントの両方の広範な構造的範囲を示した.
- この研究では,ケチミン由来アゾメチンとの最初の触媒的非対称サイクロアディションが成功裏に実証されました.
結論:
- Cu(I) -フェスルフォス触媒システムは,非対称な1,3-二極サイクロアディションのための非常に効果的なキラルルイス酸です.
- この方法論は,複雑なキラル分子のエナチオセレクティブ合成のための強力なツールを提供します.
- ケチミン由来アゾメチンの実証された有用性は,触媒的非対称サイクロアディションの適用範囲を拡大します.
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