イリジウム触媒による非活性アルケンの分子間ヒドロアミネーションとインドール
Christo S Sevov1, Jianrong Steve Zhou, John F Hartwig
1Division of Chemical Sciences, Lawrence Berkeley National Laboratory, Department of Chemistry, University of California , Berkeley, California 94720.
Journal of the American Chemical Society
|February 4, 2014
まとめ
この研究は,インドルを活性化されていないオレフィンで分子間ヒドロアミナ化することによって,N-アルキリンドールを合成するための効率的な方法を導入しています. 新しいイリジウム触媒反応は,低オレフィン過剰と良好な収穫量で進行します.
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
- 合成方法論 合成方法論
背景:
- アルキイラミンの合成は,有機化学において極めて重要です.
- 分子間ヒドロアミネーション反応は,特に活性化されていないアルケンの場合,限られており,しばしば大きな過剰を必要とします.
- 既存の方法は,活性化されていないオレフィンにN-H結合を加えるのに苦労しています.
研究 の 目的:
- 活性化されていないオレフィンを含むインドルのための新しい分子間水素アミネーション反応を開発する.
- 最小限のオレフィン等価剤を使用して,N-アルキリンドールの効率的な合成を達成するために.
- 反応機構と触媒の振る舞いを明らかにする.
主な方法:
- イリジウム触媒によるヒドロアミネーション反応.
- インドルと非活性化オレフィンを基材として利用する.
- 触媒の静止状態の特徴化,運動学的研究,同位体ラベリング.
- 反応経路を理解するための計算分析.
主要な成果:
- インドールと活性化されていないオレフィンとの分子間ヒドロアミネーションが成功しました.
- N-アルキリンドールの高収量は,わずか1.5のオレフィン等価で得られます.
- C-アルキル化に対する独占的なN-アルキル化の実証.
- 率を決定するステップとして,Ir-N結合へのオレフィン挿入の識別.
結論:
- 開発されたイリジウム触媒法では,N-アルキリンドールへの効率的な経路を提供します.
- この反応は,活性化されていないオレフィンに対する以前のヒドロアミネーション技術の限界を克服しています.
- 機理学的な研究は,オレフィンがIr-N結合に挿入することを好むことを示し,競合する経路と区別する.
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