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高度にエナチオセレクティブで,二機能のフォスフィノチオウレア酸によって触媒化されたアルネニルエステルの分子間水素アミネーション

Yuan-Qing Fang¹, Pamela M Tadross, Eric N Jacobsen

¹Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.

Journal of the American Chemical Society

|December 16, 2014

まとめ

新しい二機能性フォスフィノチオurea触媒は,アルネニルおよびプロパルギルエステルから不飽和アミノ酸エステルの高度に選択的な合成を可能にします. この触媒システムは,価値ある化学製品に対する優れた地域および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:

アミノ酸合成のための効率的な触媒システムの開発は極めて重要です.
双機能触媒は,協力的効果を通じてユニークな反応性と選択性を提供します.

研究の目的:

γ-ヒドロアミネーション反応のための新しいフォスフィノチオウレア触媒を開発する.
α,β-不飽和の γ-アミノ酸エステルの合成において高い地域およびエナチオ選択性を達成する.

主な方法:

二機能性フォスフィノチオウレア触媒を使用した.
アレニルおよびプロパルギルエステルを含むN-メトキシカルバマートヌクレオフィルを使用しています.
イソメリゼーションと結合添加を含む反応メカニズムが研究されています.

主要な成果:

アレニルエステルとプロパルギルエステルの高度に地域およびエナチオセレクティブの γ-ヒドロアミネーションを達成しました.
プロパルギルエステルからアレンリルエステルへの触媒制御されたイソメリゼーションが実証された.
高いエナチオセレクティビティに起因する協同結合添加機構を特定した.

結論:

双機能のフォスフィノチオウレア触媒は,価値あるアミノ酸誘導体を合成するのに有効です.
開発された触媒システムは,非対称合成のための正確な方法を提供します.
反応メカニズムの理解は,将来の触媒の設計のための洞察を提供します.

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