ロジウム ((III) 触媒化されたアレンとアルケンのC-H結合機能化により,インドールとピロールが生成されます
David R Stuart1, Pamela Alsabeh, Michelle Kuhn
1Centre for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Canada K1N 6N5. dstuart@fas.harvard.edu
Journal of the American Chemical Society
|December 8, 2010
まとめ
ロジウム (III) 触媒は,C-H機能化によってインドルとピロールの効率的な合成を可能にします. 最適化された条件では,分子酸素と温和な温度を使用し,基板の範囲を拡大し,生物学的活性化合物を生成します.
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
- ヘテロサイクル化学 ヘテロサイクル化学
背景:
- ロジウム (((III) 複合体,特に[Cp*RhCl (((2)) ] (((2) (1) と[Cp*Rh (((MeCN) (((3) ][SbF (((6)) ] (((2) (2) は,効果的な触媒である.
- C-H結合機能化は,複雑な有機分子を合成するための強力な経路を提供します.
研究 の 目的:
- インドルとピロルを合成するための効率的なロジウム触媒方法の開発.
- これらの触媒システムの範囲と限界を探求する.
- 反応機構を調査し,地域選択性を改善する.
主な方法:
- ロジウム触媒を用いた内部アルキンによるアセタニリドの酸化無効化.
- 温和な条件 (60°C) で,末端酸化剤として分子酸素を使用する.
- エナミドを室温で内部アルキンと触媒的に結合させる.
主要な成果:
- アセタニリドおよび内部アルキンからインドールを効率的に合成し,中等から優れた収量を得ることができます.
- 生物学的活性のあるインドル誘導体であるパウロン3の合成が成功しました.
- エナミドとアルキンから三置換ピロルの形成は,良いから優れた収量で.
- インドールとピロールの両方の合成のための高機能群互換性が実証されています.
結論:
- ロジウム ((III) 触媒は,機能化されたインドールとピロルを構築するための汎用的なプラットフォームを提供します.
- 開発された方法は,穏やかな条件,幅広い基板の範囲,そして価値あるヘテロサイクルの化合物への効率的なアクセスを提供します.
- 機械学的研究は,反応性と地域選択性に関する洞察を提供し,最適化を可能にしました.
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