シアニドなしのエナンチオセレクティブオレフィン水酸化
Alexander W Schuppe1, Gustavo M Borrajo-Calleja1, Stephen L Buchwald1
1Department of Chemistry , Massachusetts Institute of Technology , 77 Massachusetts Avenue , Cambridge , Massachusetts 02139 , United States.
Journal of the American Chemical Society
|November 6, 2019
まとめ
この研究は,ダブルパラジアム/銅の触媒を用いて,エナティオメリックに富んだニトリルを合成するための新しい,シアン化物のない方法を導入しています. このアプローチは 価値ある医薬品の中間製品への よりグリーンな経路を提供します
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- 酵素濃縮ナトリルは,医薬品合成における重要な構成要素である.
- 伝統的な水素化方法はしばしば有毒なシアン化物反応剤を含みます.
- 効率的で安全な代替品の開発は 有機合成における大きな課題です
研究 の 目的:
- オレフィンのエナチオ選択的水素化のためのシアン化物のないプロトコルを開発する.
- マルコヴニコフとアンチマルコヴニコフの両方に ニトリル等価の添加を可能にします.
- エナチオ濃縮ナトリルへのアクセスのための多用途な方法を提供する.
主な方法:
- 二重Pd/CuH触媒システムを使用した.
- オキサゾールは安全なニトリル等価物として使用された.
- [4 + 2]/レトロ- [4 + 2]解体シーケンスに続く水酸化が実施された.
主要な成果:
- ヴィニルアレンの非対称マルコフニコフ水素化が達成された.
- 末端オレフィンのアンチマルコフニコフ水酸化を有効にした.
- 軽度の反応条件下で合成されたエナチオ濃縮ニトリル.
結論:
- 開発されたプロトコルは,有価なキラルニトリルへのシアン化物のない効率的な経路を提供します.
- この方法論は,医薬品の中間製剤のための合成ツールキットを拡張します.
- オクサゾールをニトリル代替品として使用することは,従来のシアン化物源のより安全な代替品を提供します.
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