局所生成のN-カルバモイルニトロンによる有機触媒的非対称形式 [3 + 2] サイクル添加
Claudio Gioia1, Francesco Fini, Andrea Mazzanti
1Department of Organic Chemistry A. Mangini, University of Bologna, viale Risorgimento 4, 40136 Bologna, Italy.
Journal of the American Chemical Society
|June 26, 2009
まとめ
この研究は,N-BocとN-Cbzで保護されたイソキザゾリジンを合成するための新しい有機触媒反応を導入します. この方法は,容易に入手可能な触媒を使用し,高収量と純度で貴重な化学的構成要素を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・カタリシス
- 合成方法論 合成方法論
背景:
- N-カルバモイルニトロンは,一般的に1,3-二極体として生成し,利用することは困難です.
- イソクサゾリジンの非対称合成は,価値あるキラル構成要素にアクセスするために不可欠です.
研究 の 目的:
- 新しい有機触媒形式 [3 + 2]サイクロアディション反応を開発する.
- 高ダイアステロ選択性およびエナチオ選択性を持つN-Boc-およびN-Cbz-保護されたイソクサゾリジンの直接合成を達成する.
主な方法:
- N-カルバモイルニトロンのインサイト生成.
- シンコナアルカリド四分位アンモニアム塩を用いた有機触媒.
- 公式 [3 + 2] サイクル添加でグルタコナートが二極性である.
主要な成果:
- N-BocとN-Cbzで保護されたイソクサゾリジンの直接合成,単一のダイアステレオアイソマーとして.
- 一般的に高い収穫量とエナティオメリック過剰は,穏やかな条件下で達成されます.
- 製品の自由イソキサゾリジン,アミノアルコール,およびラクトームへの合成的有用性が実証されています.
結論:
- この研究は,N-カルバモイルニトロンを,非対称な触媒における電子が少ない1,3二極体として使用する先駆者となる.
- 開発された方法は,価値あるキラルイソクサゾリジン誘導体への効率的な経路を提供します.
- 触媒システムは,安価で容易に入手可能なシンコナアルカロイド誘導体に基づいています.
関連する概念動画
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