可視光による感受性刺激によるキラルアレンの触媒脱血
Alena Hölzl-Hobmeier1, Andreas Bauer1, Alexandre Vieira Silva1
1Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Garching, Germany.
Nature
|December 14, 2018
まとめ
研究者は,可視光とキラルセンシタイザーを用いて,ラセミック混合物を単一のエナチオマーに変換する光化学的方法を開発した. このプロセスは,光化学的脱塩化と呼ばれ,アレンなどのキラル化合物の高いエナチオ選択性を達成します.
科学分野:
- 有機化学
- 写真化学
- 非対称合成
背景:
- チラルの化合物はエナンチオマーとして存在し,重複できない鏡像である.
- エナチオメリックに純粋な化合物は,特に活性薬剤として極めて重要です.
- レースメート (1: 1 エナチオマー混合物) の分離は一般的ですが,エントロピックバリアのために単一のエナチオマーへの直接変換は困難です.
研究 の 目的:
- ラセマトを単一のエナンチオマーに選択的に変換する方法を開発する.
- 可視光とキラルセンシタイザーを用いて光化学的脱血の可行性を調査する.
- アシメトリーを作り出すという課題に取り組むために
主な方法:
- キラルセンシティザーの触媒量 (2.5 mol%) の存在で可視光照射 (420 nm) を利用する.
- この方法を17のキラル・ラセミック・アレンの範囲に適用する.
- センシタイザーからアレンへの三重エネルギー伝達を含むメカニズムを仮定する.
主要な成果:
- キラル化合物の脱血で高いエナチオセレクティビティを達成した.
- 17種類のキラル・ラセミック・アレンをそれぞれの単一のエナティオマーに変換した.
- 89%から97%までのエナティオメール過量が得られた.
結論:
- 光化学的脱血は,ラセミック混合物からエナチオプア化合物を生成するための有効な方法である.
- キラルセンシタイザーは 単方向の触媒として 光エネルギーによって駆動され エントロピー不快を克服します
- このアプローチは,分子不対称性を作るという課題に取り組んで,エナチオピュア材料の直接的形成のための新しい戦略を提供します.
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