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Updated: Jul 23, 2025

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活性化されていないアレーンの非対称な触媒Friedel-Crafts反応

Sebastian Brunen¹, Benjamin Mitschke¹, Markus Leutzsch¹

¹Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany.

Journal of the American Chemical Society

|July 13, 2023

まとめ

この研究では,活性化されていないアレンに対する新しい非対称なフリーデル・クラフト反応が導入され,エナチオ濃縮されたアリルグリシンエステルの合成が可能になった. この突破は単純なアルキルベンゼンの非対称な触媒の範囲を拡大します.

科学分野:

有機化学
カタリシス
非対称合成

背景:

フライデル・クラフト反応は,アレーンに炭素置換素を導入するための基石である.
非対称的な変種でのその適用は,アレン核愛性の制約のために活性化基板に制限されています.

研究の目的:

活性化されていないアレンに適用できる非対称なフリーデル・クラフト反応を開発する.
単純な炭化水素アレンからエナチオ濃縮されたアリルグリシンエステルの合成を可能にします.

主な方法:

強いBrønsted酸の有機触媒を使用した.
N,O-アセタルは電愛性パートナーとして使用されている.
活性化されていないアレン,アルコキシベンゼン,およびヘテロアレンとの反応を調査した.

主要な成果:

地域とステレオ選択性の高いC-C結合形成を達成した.
単純なアルキルベンゼンで最初の非対称な触媒Friedel-Crafts反応を成功させた.
以前にアクセシブルな基板からエナチオ濃縮されたアリルグリシンエステルを生成した.

結論:

非対称なフリーデル・クラフト反応における基板核好性の制限を克服した.
非対称な有機触媒を用いてフリーデル=クラフトのアルキル化の有用性を拡大した.
有機化学における非対称合成のより広範な応用への道を開いた.

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