N-メトキシヘテロアレニウム塩を用いた非活性アルケンの水分エロアリレーション
Xiaoshen Ma1, Hester Dang1, John A Rose1
1Department of Chemistry, Yale University , New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|April 1, 2017
まとめ
この研究は,水素原子移転条件下でN-メトキシヘテロアレニウム塩を使用して,活性化されていないアルケンのための新しい還元結合法を導入しています. この多用途な反応は,様々な基質に対して独占的な単塩基化と高い地域選択性を提供します.
科学分野:
- 有機化学
- ラジカル・ケミストリー
- 合成方法論
背景:
- 還元結合反応は,有機合成におけるC−C結合形成に不可欠である.
- 活性化されていないアルケンを結合する方法を開発することは依然として大きな課題です.
- 水素原子移転 (HAT) は,過激な生成と機能化のための強力なメカニズムです.
研究 の 目的:
- N-メトキシピリダジニウム,イミダゾリウム,キノリニウム,イソキノリニウム塩との最初の還元結合を報告する.
- N-メトキシピリジニウム塩とのアルケンの結合の範囲を拡大する.
- これらの新しい変換の地域選択性と範囲を調査する.
主な方法:
- 商用前駆体から様々なN-メトキシヘテロアレニウム塩の合成.
- 水素原子移転 (HAT) 条件を用いた還元結合反応.
- 反応産物の産量,単塩基化,および地域選択性に関する分析.
- 異なる基質型の補完的なサイト選択性の探査
主要な成果:
- N-メトキシヘテロアレニウム塩と38の異なるアルケンの結合を成功させた.
- ニュートラルな環境条件下での単一アルケンの付加地域同位体形成.
- C-2とC-4の添加を好む,二次的および三次的ラジカルのための準備的に有用なサイト選択性を実証した.
- より置換されたアルケンのダイエンの排他的水酸化.
- メトキシピリジニウム塩の脱水性アリレーション,ボロノ-ミニシ,およびタンデムアリレーションでの成功.
結論:
- 活性化されていないアルケンの還元結合のための新しく汎用的な方法が確立されています.
- 開発された方法論は,単塩基化と地域選択性に対する優れた制御を提供します.
- N-メトキシヘテロアレニウム塩は,アリレーションおよびミニシ型反応を含む,激素媒介変換のための貴重な構成要素である.
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