リガンド活性化メタ-C-Hアルキレーションと修正されたノルボネンを用いたアリレーション
Peng-Xiang Shen1, Xiao-Chen Wang1, Peng Wang1
1Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
Journal of the American Chemical Society
|August 28, 2015
まとめ
新しい一時的媒介体である2-カルボメトキシノルボルネンは,パラジウム触媒によるC-Hアルキレーションとアライレーションを強化する. この効率的な合成変換にはカスタムキノリンのリガンドも重要です
科学分野:
- 有機化学
- キャタリシス
背景:
- パラジウム触媒によるC-H機能化は 有機合成の強力なツールです
- アミドのメタ-C ((sp2) -H機能化の効率的な方法の開発は依然として困難である.
研究 の 目的:
- アミドのパラジアム触媒化メタ-C ((sp2) -Hアルキル化およびアリレーションのための効果的な一時的な媒介体を特定する.
- 以前は互換性のないカップリング・パートナーのための強力な触媒システムを開発する.
主な方法:
- 2-カルボメトキシノルボネンを一時的な媒介物として利用する.
- Pd (II) 触媒反応において,特製のキノリンリガンドを使用する.
- 様々なアルキル・イオジドとアリル・イオジドをアミドと結合させるためのスクリーニング
主要な成果:
- 2-カルボメトキシノルボネンは,一時的なメディエーターとして優れた性能を示した.
- 触媒システムは,様々なアルキルイオジでメタ-C ((sp2) -Hアルキル化を成功裏に促進した.
- この反応により,以前はこのような変換に適合しなかったアリルヨウ素を用いたアリレーションが可能になった.
- 高い効率と選択性を達成するためにカスタムキノリンリガンドは不可欠でした.
結論:
- 2-カルボメトキシノルボネンは,アミドのPd-触媒メタ-C ((sp2) -H機能化の非常に効果的な一時的な媒介物である.
- 開発された方法論は,挑戦的な基質を含むC-Hアルキル化とアリレーションの範囲を拡大します.
- 媒介体と特殊なリガンドの組み合わせは,合成有機化学において貴重な進歩をもたらします.
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