ルイス酸によるキラルβ置換アミドの銅触媒による非対称合成
Mamen Rodríguez-Fernández1, Xingchen Yan1, Juan F Collados1
1Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|September 30, 2017
まとめ
この研究では,銅とルイス酸を用いた新しい触媒法が,アルキル化のための非反応性エナミドを活性化する. このプロセスは,挑戦的なメチル化でも,高収量とステレオ制御を達成します.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- エナミドは通常,オルガンマグネシウム反応剤によるアルキル化に反応しない.
- これらの複雑な基質を活性化するための触媒的方法の開発は,合成化学にとって極めて重要です.
研究 の 目的:
- 活性化されていないエナミドにオルガン・マグネシウム反応剤を加えた触媒的非対称結合剤を開発する.
- エナミドの固有の低反応性を克服し,高い化学的およびステレオ選択性を達成する.
主な方法:
- 簡単に手に入るシリルとボロンベースのルイス酸を,キラル銅触媒と組み合わせて利用する.
- エナミドのアルキル化のためにオルガンマグネシウム反応剤を使用する.
- 反応範囲,温度耐久性,そして触媒の再利用性を調査する.
主要な成果:
- エナミドへの触媒的非対称結合添加で 卓越した化学反応性とステレオ制御を達成した.
- 前例のない反応範囲が示され,良い収穫量と優れたエナチオ選択性を持つ挑戦的なメチル化が含まれています.
- 広範囲の温度 (−78°Cから環境温度) とスケールアップ (10g) に応じて再利用可能と耐性を示した.
結論:
- 開発された触媒プロトコルは,非反応性エナミッドを非対称アルキル化のために効果的に活性化します.
- 機理学的な研究は,ルイス酸の役割を特定し,触媒のサイクルを明らかにした.
- この方法は,特に挑戦的な基質のエナチオセレクティブ合成のための強力な新しいツールを提供します.
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