主要なカルボキシアミドの効率的なトランスアミデーションは,N,N-ダイアルキルフォームアミドジメチルアセタールとインシット活性化によって行われます
Thomas A Dineen1, Matthew A Zajac, Andrew G Myers
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Journal of the American Chemical Society
|December 15, 2006
まとめ
アミド合成のための新しい方法により,一次アミドの効率的なトランスアミド化が可能になります. これらのプロトコルでは,N,N-ダイアルキルホルマミドジメチルアセタールとルイス酸添加物を利用して,高収量アミド交換反応を行う.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成方法論 合成方法論
背景:
- アミド結合形成は有機合成において極めて重要です.
- トランスアミデーションは,アミドへの代替経路を提供します.
- アミドトランスアミデーションの既存の方法には限界があります.
研究 の 目的:
- 主要アミドの効率的なトランスアミド化のための新しいプロトコルを開発する.
- アミド交換反応を促進するルイス酸添加物の使用を調査する.
主な方法:
- N,N-ダイアルキルホルマミドジメチルアセタルを用いて,N'-アシル-N,N-ダイアルキルホルマミジン中間物質を形成するプライマリアミドの活性化.
- 2つの異なるプロトコル:一つは中間製品の浄化,もう一つは in situ 生成.
- スカンジウムトリフラートやジルコニウム塩化物などのルイス酸を用いて,アシル移転を促進する.
主要な成果:
- トランスアミド化により得られた二次および三次アミドの高収量.
- ルイス酸添加物の有効性が,不可逆的なアミジニル移転を克服する上で実証された.
- 様々な原始アミドとアミンの成功応用.
結論:
- アミドトランスアミデーションのための2つの効率的で汎用的なプロトコルを開発しました.
- これらの方法は,アミドを合成するための貴重な新しいツールを提供します.
- ルイス酸の使用は,これらのトランスアミデーション反応の成功の鍵です.
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