キラルヌクレオフィリックピリジン触媒の開発:非対称四次炭素合成における応用
Scott A Shaw1, Pedro Aleman, Edwin Vedejs
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Journal of the American Chemical Society
|October 30, 2003
まとめ
新しいキラル触媒であるTADMAPは,アズラクトンやオキシンドールなどの有価な化合物のエナチオセレクティブ合成を可能にします. この触媒は,高い収量とエナティオメア過剰を持つ重要な化学変化を促進します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- アシンメトリック・シンセシス
背景:
- 4 - ダイメチラミノピリジン (DMAP) は,広く使用されている核愛性触媒です.
- キラルなDMAPアナログの開発は,非対称な触媒にとって極めて重要です.
- 複雑な分子のステレオセレクティブ合成は,有機化学における重要な課題です.
研究 の 目的:
- 新しいキラル型DMAP触媒,TADMAPを設計・合成する.
- エナチオセレクティブ再配列におけるTADMAPの触媒活性を調べる.
- 様々なキラル化合物を合成するTADMAPの範囲を調査する.
主な方法:
- TADMAPの合成には,トリフェニル酸エステン酸と (ジメチラミノ) ピリジンから始まる4段階の手順が必要でした.
- TADMAPのキラル解像度は,カンフォルスルフォン酸を用いて達成された.
- TADMAPを使用して,オクサゾリルフェニル炭酸,フーラニルフェニル炭酸,ベンゾフーラニル炭酸,およびインドリル炭酸を含む様々な基板とのエナチオセレクティブ再配列反応が行われました.
主要な成果:
- TADMAPの合成と解消が成功しました.
- TADMAPは,オクサゾリルフェニル炭酸のエナチオセレクティブによるアズラクトンへの再構成を効果的に触媒化した.
- 触媒はまた,フーラニルフェニル炭酸をフーラノンに,ベンゾフーラニル炭酸をベンゾフーラノンに,インドリル炭酸をオキシンドールに,良好な生産性とエナティオメール過剰で再配置することを促進しました.
結論:
- TADMAPは,エナチオセレクティブの再編成のための非常に効果的なキラル触媒です.
- TADMAPの設計されたキラル環境は,四次炭素中心の形成において高いステレオ選択性を促進します.
- この触媒は,重要なヘテロサイクリック化合物の非対称合成のための貴重なツールを提供します.
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