角的に置換された1-アザビサイクルリングシステムのエナチオセレクティブ合成: aza-Copeの再配置を用いた動的運動解像度
Tatsuya Ito1, Larry E Overman, Jocelyn Wang
1Department of Chemistry, University of California, Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025, USA.
Journal of the American Chemical Society
|February 24, 2010
まとめ
新しいエナチオセレクティブ合成により,高収量で99%のエナチオメリック過剰 (ee) を有する,角的に置換された1-アザビサイクリックアミンが得られます. この方法は,効率的なステレオ選択合成のためのユニークなダイナミック・キネティック解像度戦略を使用しています.
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
- ステレオ化学 ステレオ化学
背景:
- 1-アザビサイクルの分子は,医薬品化学における重要な支架である.
- 効率的なエナチオセレクティブ合成経路の開発は,純粋なステレオアイソマーにアクセスするために不可欠です.
研究 の 目的:
- 角的に置換された1-アザビサイクリック分子の新種のエナンチオセレクティブ合成を報告する.
- 合成されたバイサイクルアミンの高収量とエナティオメール過剰 (ee) を達成するために.
主な方法:
- サイクロアルカノンとエナティオメリカルに純粋な (R) - 2 - フェニル - 3 - ブテナミンから5つのステップで起料の組み立て.
- 動的運動解像度を含むカスケード変換の適用.
- イミニウムカチオンの急速なタウトメア均衡と,ダイアステレオ選択的シグマトロピク再配置の組み合わせ.
主要な成果:
- 角的に置換されたcis-octahydrocyclopenta[b]pyrroles,cis-octahydroindoles,cis-decahydrocyclohepta[b]pyrroles,およびcis-octahydrocyclopenta[b]pyridineの合成に成功し,良好な収穫量と99% ee.
- ほとんどのバイサイクルの製品では,CISステレオアイソマーの独占的形成.
- デカヒドロキノリンの生成は,高EEを持つシスおよびトランスステレオアイソマーの混合物として行われる.
結論:
- 開発されたエナチオセレクティブ合成は,動的運動解像度のための新しい戦略を提供します.
- このアプローチは,ステレオ化学的に定義された価値ある1-アザビサイクルの化合物への効率的なアクセスを提供します.
- この方法論は,サイクリックケトン起料の範囲に適用できます.
関連する概念動画
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