光誘導による電子移転によって引き起こされる触媒的エナチオセレクティブ反応

Andreas Bauer¹, Felix Westkämper, Stefan Grimme

¹Lehrstuhl für Organische Chemie I, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching, Germany.

Nature

|August 27, 2005

まとめ

この研究は,キラル分子を作るための触媒的光誘導電子移転法を導入しています. 新しいアプローチでは,キラル有機触媒を用いて,高エナチオセレクティブ性と非対称合成の収量を得ています.

科学分野:

フォトケミストリーフォトケミストリー
有機化学オーガニック・ケミストリー
アシンメトリック・シンセシス

背景:

光誘発電子移転 (PET) は,太陽エネルギー変換と化学合成に不可欠です.
PET反応における興奮状態の寿命は短いため,製品形成の制御が困難になり,特にエナチオピュア化合物は困難です.
エナンチオセレクティブPETの既存の方法は,しばしばステキオメトリックキラル剤に依存しています.

研究の目的:

高回転率とエナチオセレクティビティを持つ触媒的光誘導電子移転反応を開発する.
光駆動の電子移転を用いたキラル化合物の効率的な非対称合成を可能にする.

主な方法:

電子受容体としてキラル有機触媒を使用した.
水素結合を用いて,基板の周りにキラルな環境を作り出しました.
光誘導電子移転反応における触媒的ターンオーバーとエナチオ選択性を研究した.

主要な成果:

光誘導電子移転反応において,有意な触媒周回率を達成した.
高いエナティオメール過量 (最大70%まで) を有する製品を取得します.
64%の生産率を達成しました.

結論:

非対称合成のための新しい触媒PET反応を実証した.
キラル有機触媒は,水素結合によってエナチオセレクティビティを効果的に制御した.
光化学的経路は,キラル化合物の一般的な非対称合成の有望性を示しています.

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