ボロナート複合体のフッ化によるエナチオ濃縮アルキルフッ化物の合成
Christopher Sandford1, Ramesh Rasappan1, Varinder K Aggarwal1
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|August 6, 2015
まとめ
チラルの二次ボロンエステルは,ボロナート複合体とセレクトフローアIIを用いてアルキルフッ素に効率的に変換される. この方法は,高エナチオ特異性を達成し,エナチオ純粋フッ素化合物の合成に不可欠です.
科学分野:
- 有機化学
- 化化学
- ステレオ選択合成
背景:
- チラルアルキルフッ素は,医薬品と農薬の重要な構成要素である.
- 合成のための効率的でステレオ選択的な方法の開発は依然として課題です.
研究 の 目的:
- キラル二次ボロンエステルをアルキルフッ化物に変換するための新しい方法について報告する.
- 電子性化における核愛素としてのボロナート複合体の使用を調査する.
主な方法:
- 核愛者として,ボロンエステルとPhLiから生成されたボロナート複合体を利用した.
- 電気的化剤としてSelectfluor IIを使用した.
- エナチオ特異性を高めるためのラジカル・トラップとしてのスタイレンの効果を調査した.
主要な成果:
- キラル二次ボロンエステルのアルキルフッ化物へのエナンチオ固有の変換を達成した.
- フッ素化プロセスの反応時間は短いことが証明されています.
- 幅広い基板でほぼ完全なエナンチオ特異性が見られた.
結論:
- 開発された方法は,エナチオメリックに富んだアルキルフッ素への効率的な経路を提供します.
- ボロナート複合体とSelectfluor IIの使用は,ステレオ選択的化のための貴重なツールを提供します.
- 反応のステレオ化学的結果を改善するために,ラジカルトラッピングは有益です.
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