酸化性陽子結合電子移転によって活性化された触媒性アルケンの炭酸アミネーション
Gilbert J Choi1, Robert R Knowles1
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|July 14, 2015
まとめ
この研究では,協調型陽子結合電子移転 (PCET) を使用したN-アリラミドにおける選択的なN-H結合同解のための新しい二重触媒システムを導入しています. この方法は,カルボアミネーションのためのアミドールラジカルを効率的に生成し,複雑なヘテロサイクルを生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- フォトカタリシスによる.
- 合成方法論 合成方法論
背景:
- アミドN-H結合は典型的には強く,機能化が困難である.
- 弱いC-HボンドよりもN-Hボンドの選択的活性化が難しい.
- 協調型陽子結合電子移転 (PCET) は,生物学的酸化還元プロセスにインスパイアされています.
研究 の 目的:
- N-アリラミドにおける選択的N-H結合同解のための二重触媒システムを開発する.
- 生成されたアミジルラジカルの効率的なカルボアミネーションを達成するために.
- 単純なアミド前駆体から構造的に複雑なヘテロサイクルを合成する.
主な方法:
- イリジウム光触媒と弱いリン酸塩基を用いた.
- N-H結合の活性化のために,協調された陽子結合電子移転 (PCET) を採用した.
- 反応の合成範囲とメカニズム的側面を調査した.
主要な成果:
- N-H結合の選択的同解 (∼100 kcal/mol) が,より弱いアリル系C-H結合の存在下で達成される.
- アミジルラジカルの効率的なカルボアミネーションが実証されています.
- 様々な複雑なヘテロサイクリック化合物を合成した.
結論:
- 開発されたPCETベースの二重触媒システムは,選択的なN-H結合活性化と,その後の炭酸アミネーションを可能にします.
- この方法論は,容易に入手可能なアミドから複雑なヘテロサイクルのための汎用的な経路を提供します.
- この発見は,PCETメカニズムと合成化学におけるその応用に関する洞察を提供します.
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