動的運動解像度によるQUINAPの非対称合成
Vikram Bhat1, Su Wang, Brian M Stoltz
1Caltech Center for Catalysis and Chemical Synthesis, Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California, 91125, United States.
Journal of the American Chemical Society
|October 25, 2013
まとめ
パラジウムで触媒化された新しい方法により,重要なQUINAPリガンドと誘導体の高選択性の非対称合成が可能になりました. この効率的なプロセスは,低触媒負荷を利用し,これらの価値あるキラルフォスフィン結合体への簡単な経路を提供します.
科学分野:
- 有機金属化学 有機金属化学
- アシンメトリック・カタリシス
- リガンド合成 リガンド合成
背景:
- QUINAPのようなキラル・フォスフィン・リガンドは,エナチオメリックに純粋な化合物を生成するための非対称合成において極めて重要です.
- これらのリガンドを合成するための効率的で選択的な方法の開発は,触媒的アプリケーションを前進させるために不可欠です.
- 以前の方法は,収量,選択性,または触媒効率の制限に苦しんでいる可能性があります.
研究 の 目的:
- QUINAPおよびその誘導体の非対称合成のためのアトロポセレクティブC-Pカップリングプロセスを開発する.
- パラジウム触媒結合反応のための様々な脱出基 (ブロミド,トリフラート,OSs) を探求する.
- 低パラジウム触媒負荷を使用して高エナティオメア過剰と収穫量を達成するために.
主な方法:
- パラジウムで触媒化されたCP結合反応.
- 異なる前駆物質のスクリーニング:ブロミド,トリフラート (OTf),および4-メタネスルフォニルベンゼンスルフォネート (OSs).
- 反応条件の最適化により,アトロポセレクティビティと高収量を得る.
主要な成果:
- QUINAPおよびその誘導体の非対称合成が成功し,高エナティオメア過剰が認められた.
- アリルパラジウム中間イソメリゼーションによる新しい動的運動解像度につながる前駆体としてトリフラートの識別.
- 低触媒負荷 (≤3 mol % Pd) を使って,良好から高い収量と選択性を達成します.
結論:
- QUINAP合成のために,新しく,操作的にシンプルなパラジウム触媒によるアトロポセレクティブC-P結合法が確立されています.
- 開発された方法は,優れたエナチオセレクティブ性を持つ有価なキラル・フォスフィン・リガンドへの効率的なアクセスを提供します.
- この発見は,改善されたリガンド合成戦略を通じて,非対称な触媒の進歩に寄与する.
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