エアロビック Pd-触媒 sp3 C-H オレフィネーション: N-ヘテロサイクリック・スキャフォールドとアルケーンの両方への経路
Kara J Stowers1, Kevin C Fortner, Melanie S Sanford
1Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, USA.
Journal of the American Chemical Society
|April 12, 2011
まとめ
新しいパラジウム/ポリオキシメタラート法により,窒素ヘテロサイクルの使用により,C−H結合の有酸素オレフィネーションが可能になる. このアプローチは,過度の機能化を防止し,さらなる合成のための貴重なバイサイクリック・スキャフォルドとオレフィンを生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- 活性化されていない sp ((3) C-H 結合の直接的機能化は,有機合成における重要な課題である.
- C-Hオレフィネーションのための効率的で選択的な方法の開発は,複雑な分子を作るために非常に重要です.
研究 の 目的:
- 活性化されていないsp(3) C-H結合の有酸素オレフィネーションのための新しい触媒システムを導入する.
- パラジウム触媒によるC-H機能化における導向群として窒素ヘテロサイクルを利用する.
- 望ましい製品の過剰な機能化を防ぐ方法を開発する.
主な方法:
- パラジウム/ポリオキソメタラート (Pd/POM) 触媒システムを採用しています.
- 空気をエアロビックオレフィネーションの末端酸化剤として利用する.
- 製品保護のために,リバーシブルな分子内ミカエル添加を活用する.
主要な成果:
- 窒素ヘテロサイクルの指示による非活性化されたsp ((3) C-H結合の有酸素オレフィネーションが成功しました.
- モノアルケニル化製品は,可逆的なマイケルの添加によって過度の機能化から保護されます.
- マイケル・アダクトの水素化を介して,バイサイクル窒素を含有する支架へのアクセス.
- さらに合成加工のためにα,β不飽和オレフィンの生成.
結論:
- 開発されたPd/POM触媒方式は,選択的C-Hオレフィネーションのための新しい経路を提供します.
- この戦略は,価値ある中間物質と複雑な分子構造の合成を可能にします.
- このアプローチは,C-H機能化と天然製品の合成のためのツールキットを拡張します.
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