核性ベータ-オニオニビリレーション:概念,メカニズム,範囲,応用
Robert Weiss1, Matthias Bess, Stefan M Huber
1Department of Chemistry and Pharmacy, Organic Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestrasse 42, D-91054 Erlangen, Germany. weiss@chemie.uni-erlangen.de
Journal of the American Chemical Society
|March 18, 2008
まとめ
研究者らは,電子欠乏性アルキンを初めてアシル・オニオ塩に挿入した. この新しい反応は,多様な化学的変換の可能性を持つ,ユニークなベータオニオ活性化ミカエル系を生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 合成化学 合成化学とは
背景:
- アシル-オニオ塩は,有機合成における多用途の中間物質である.
- 電子欠乏アルキンのアシルオニオ塩におけるC-L+結合の反応性は,ほとんど未研究のままである.
研究 の 目的:
- 電子欠乏性アルキンをアシルオニオ塩のC-L+結合に初めてうまく挿入した.
- この新しい反応のステレオ化学的結果とメカニズム的経路を探求する.
- 結果として生じるベータオニオ活性化マイケルのシステムの合成的有用性を調査する.
主な方法:
- アシル-オニオ塩 (R-C(O) -L+) と電子欠乏性アルキン (A-CC-A) の反応は,触媒核愛素 (L) の存在による.
- X線結晶学を用いた製品の特徴化.
- 反応経路とステレオ化学制御の解明のためのメカニズム研究.
主要な成果:
- 電子欠乏性アルキンをアシル・オニオ塩に初めて成功裏に挿入した.
- 特定の基板 (R=OMe) のための第2回アルキン挿入の観察.
- 熱力学的に好ましいZ同位体であるベータ-オニオニビリレーション製品におけるE/Z立体化学の決定.
- ベータ・オニオで活性化されたミカエルシステムの新しいクラスの生成.
結論:
- ベータオニオで活性化されたマイケルのシステムへの新しい合成経路が確立されました.
- オニオの置換剤は選択的に置き換えることができ,多様なミカエル系を簡単に合成することができます.
- これらの化合物は,キノロン,チオクロモン,ピラゾールなどのヘテロサイクルへのサイクル化を含む,さらなる変換のための貴重な前駆体として機能します.
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