オレフィンの反熱力学的位置性同体化
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|December 30, 2021
まとめ
この研究は,安定したオレフィンを,より不安定な同位体へと変換する,新しい光駆動によるオレフィンの同位体化の方法を導入している. このプロセスは,光還元触媒とクロム共触媒を使用して,反熱力学的変換を実現します.
科学分野:
- 有機化学
- 写真化学
- カタリシス
背景:
- オレフィン同体化は有機合成において極めて重要です.
- 特に代替オレフィンについては,反熱力学的イソメリゼーションを達成することは依然として困難です.
- 既存の方法はしばしば効率的でないか,基板の範囲がない.
研究 の 目的:
- オレフィンの反熱力学的位置性イソメリゼーションのための光駆動方法を開発する.
- 熱力学的に安定していないアルケンの同位体合成を可能にします.
- オレフィン異体化反応のための基板の範囲を拡大する.
主な方法:
- オレフィン基板の段階的な陽子結合電子移転 (PCET) 活性化
- 興奮状態の酸化物質と ブロンステッド塩基を用いて
- アリルクロム (III) の中間物質を形成するために,Cr (II) コカタリストを使用する.
- メタノールを用いた地域選択的プロトデメタレーション.
主要な成果:
- オレフィンの光による反熱力学的位置性イソメリゼーションの成功
- アリル基の中間物質の形成と捕獲
- 熱力学的に安定していないアルケンの産物の高度な地域選択合成.
- エノールエーテル,エナミド,スタイレン,1,3-ダイエン,テトラ置換アルキルオレフィンを含む,実証された基板範囲.
- オレフィンの慣性性により,代謝が少ない,安定性が低い同位体が蓄積される.
結論:
- 開発された方法は,熱力学的に不利なオレフィン同位体への効率的な経路を提供します.
- フォトレドックス触媒によるアプローチは,オレフィン機能化のための汎用的なプラットフォームを提供します.
- プロトデメタレーションの段階に関するメカニズム的な洞察が得られた.
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