イリジウム触媒型エナチオセレクティブ・アリル置換と核愛性の水溶液
Tobias Sandmeier1, F Wieland Goetzke1, Simon Krautwald1
1ETH Zürich , Vladimir-Prelog-Weg 3 , HCI, 8093 Zürich , Switzerland.
Journal of the American Chemical Society
|July 19, 2019
まとめ
イリジウム触媒は,不安定な核愛素を用いた非対称なアリル置換を可能にします. この方法は,高いステレオ選択性を持つ多様なキラル化合物を効率的に生成します.
科学分野:
- 有機金属化学
- 非対称な触媒
- 合成有機化学
背景:
- 非対称性アリル置換はキラル分子を作るための強力なツールです.
- このような反応で不安定なまたは揮発性のある核愛素を使用することは,重要な課題を提示します.
- 二相触媒システムは,反応性の種を扱うのにユニークな利点を提供します.
研究 の 目的:
- イリジウム触媒による非対称性アリル置換プロトコルの開発
- 不安定なおよび/または揮発性のある核好物の幅広い使用を可能にします.
- 高い収量と優れたステレオ制御を実現します.
主な方法:
- 非対称性アリル置換反応のイリジウム触媒を使用する.
- 多様な核愛者を収容するために二相反応システムを利用する.
- 標準的な分析技術 (NMR,HPLCなど) を用いて製品の特徴づけ ) でした.
主要な成果:
- 様々な不安定な核性物質:ヒドラジン,メチアミン,t-ブチル水酸化物,N-ヒドロキシアミン,α-クロロアセタルデヒド,およびグルタルデヒドの成功応用.
- 高い収穫量と優れたエナチオ選択性 (> 99% ee) が達成されました.
- 高いダイアステレオ選択性 (20:1 d.r.まで) 観察されました.
- 4つのステレオセンターを持つ複雑なサイクルおよび非サイクル化合物へと効率的に精製されました.
結論:
- 報告されたイリジウム触媒による二相非対称アリル置換は,多用途で効率的な方法である.
- シンプルな前駆体から貴重なキラル・ビルディングブロックに迅速なアクセスを提供します.
- この方法論は,複数のステレオセンターを持つ複雑な分子の合成を容易にする.
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