メタロラジカルC−Hアルキレーションによる5つ組のリング構造の構築のためのエナチオセレクティブ・ラジカルサイクリング
Yong Wang1, Xin Wen1, Xin Cui2
1Department of Chemistry, Merkert Chemistry Center , Boston College , Chestnut Hill , Massachusetts 02467 , United States.
Journal of the American Chemical Society
|March 28, 2018
まとめ
研究者らは,飽和C−H結合を用いたラジカルサイクリングのための新しいコバルト触媒方法を開発した. このアプローチにより,単純なアルデヒドからキラルピロリジンおよび他の五連鎖の合成が可能である.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- リング構造の合成には 根本的なサイクルが不可欠です
- 従来の方法は不飽和基板を必要とし,その範囲を制限します.
- すぐ手に入る飽和C−H結合を利用するための新しい戦略が必要である.
研究 の 目的:
- 飽和C−H基板を用いた新種の触媒システムを開発する.
- 有用なサイクル化合物のエナチオセレクティブ合成を達成する.
- 5つ組のリングの構築のための新しいレトロ合成アプローチを確立する.
主な方法:
- コバルト (II) 基の触媒システムの開発
- アリファティック・ディアゾ化合物の触媒活性化
- C ((sp3) -H結合のエナンチオセレクティブ・ラジカルアルキル化
主要な成果:
- キラル・ピロリジンや他の5つ構成のサイクル化合物の効率的な構築
- 飽和した基質を用いた新しい基質循環の実証.
- C−HとC=Oの元素の結合が成功し,C−C結合が形成される.
結論:
- 開発されたCO2ベースのシステムは,従来の急性サイクリングに強力な代替手段を提供します.
- この方法論は,キラルサイクル分子にアクセスするための新しいレトロ合成パラダイムを提供します.
- このアプローチにより,単純な開鎖アルデヒドから有価な5つ組の環を合成することができる.
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