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メソエポキシドとアリルハリドのエナチオセレクティブ・クロスカップリング
1Department of Chemistry, University of Rochester , Rochester, New York 14627-0216, United States.
Journal of the American Chemical Society
|February 27, 2015
まとめ
この研究は,アリルブロミドとメソエポキシドの新たなエナチオセレクティブ結合を導入し,トランス-β-アリルサイクロアルカノールを生成します. この触媒的方法は,様々な基板に対して,高い収量と優れたエナティオメリ余剰を提供します.
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
- アシンメトリック・シンセシス
背景:
- エナチオセレクティブ合成は,医薬品と微細化学品にとって極めて重要です.
- キラルアルコールを作るための効率的な方法の開発は,有機合成における重要な課題です.
研究 の 目的:
- アリルブロミドとメソエポキシドの間の最初のエナンチオセレクティブのクロスエレクトロフィール結合反応を開発する.
- 高いエナティオメリック純度を持つトランス-β-アリルサイクロアルカノールを合成する.
主な方法:
- この反応は, (bpy) NiCl2 と,還元条件下でキラルチタノセンを含む触媒システムを使用します.
- 様々な機能群を持つメソエポキシドと共に,様々なアリルおよびビニルハライドを試験した.
- 反応経路を調査するために,サイクロオクトン一酸化物変換を含むメカニズム研究が行われました.
主要な成果:
- 収量は57~99%で,エナティオメルの過剰は78~95%の範囲で得られた.
- 反応の広範な範囲を30例で示し,様々な機能群 (エーテル,エステル,ケトン,ニトリル,ケタル,トリフルオロメチル,スルフォナミド,スルフォナートエステル) を取り入れました.
- 特定のサイクロオクテン一酸化物変換を通じて,炭素ラジカル間接性の証拠を提供した.
結論:
- トランス-β-アリルサイクロアルカノールへの新たなエナンチオセレクティブ経路を成功裏に確立しました.
- 開発された触媒システムは,効率的で汎用性があり,幅広い基板に適用できます.
- この発見は,非対称な触媒の分野を前進させ,キラル分子を合成するための貴重なツールを提供します.
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