非対称クロスカップリング反応におけるオルガノチタニウム核性物質:キラルα-CF3チオエーサーのステレオコンバーゲント合成
Andrii Varenikov1, Mark Gandelman1
1Technion - Israel Institute of Technology , Technion City, Haifa 3200008 , Israel.
Journal of the American Chemical Society
|July 2, 2019
まとめ
オーガノチタニウム反応剤は,キラルな有機分子を作るための新しい非対称なクロスカップリング反応を可能にします. この研究は,薬剤発見に価値のあるトリフローロメチル化チオエーテルを合成する際に使用することを紹介しています.
科学分野:
- 有機化学
- カタリシス
- 薬剤化学
背景:
- 非対称な触媒は,キラル有機化合物の合成に不可欠です.
- ニッケル触媒によるクロスカップリング反応は,ステレオ選択的合成のための強力なツールである.
- オルガノチタニウム反応剤は,これらの反応における核愛素として以前は調査されていませんでした.
研究 の 目的:
- 非対称クロスカップリング反応における新しい核愛性結合パートナーとしてオルガノチタニウム種を導入する.
- CF3 置換型チオエーテルを初めて非対称的に合成する.
- オーガノチタニウム反応剤の有効性を,従来のオーガノマグネシウムおよびオーガノジン製の反応剤と比較する.
主な方法:
- 非対称なニッケル触媒を用いて交互結合反応を行う.
- オルガノチタニウム種を核愛体として使っている.
- チオエーテル合成のためのステレオコンバージェント反応の開発
主要な成果:
- アシンメトリック・クロスカップリングにおけるオルガノチタニウム種の成功例を初めて実証した.
- トリフローロメチル (CF3) 置換型チオエーテルを初めて非対称的に合成した.
- オルガノチタン反応剤は,オルガノマグネシウムおよびオルガノジン反応剤と比較して有益な性質を示した.
結論:
- オルガノチタニウム反応剤は,非対称的なクロスカップリングのための新しいクラスである.
- この方法論は,エナチオ濃縮フッ素チオエーテルへの効率的なアクセスを提供します.
- 合成された化合物は,新しい医薬品と農薬を開発する可能性を秘めています.
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