レーニウム (V) -オクソ複合体によって触媒化されたイミンのエナチオ選択的還元
Kristine A Nolin1, Richard W Ahn, F Dean Toste
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|September 8, 2005
まとめ
新しいキラルレニウム触媒は,N-フォスフィニルイミンのエナチオセレクティブ水酸化を可能にします. この空気と水分に耐える方法は,高エナチオセレクティブ性を持つ多様なイミン基板を効率的に削減します.
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
- 合成有機化学 合成有機化学について
背景:
- エナチオセレクティブ合成は,医薬品と微細化学品にとって極めて重要です.
- 非対称変換のための堅牢で効率的な触媒システムの開発は,依然として重要な課題です.
- 水酸化は,キラルアミンおよび関連する化合物への多用途な経路を提供します.
研究 の 目的:
- N-フォスフィニルイミンのエナチオセレクティブ水溶化のための新しい空気と水分に耐える触媒システムを開発する.
- 開発された触媒システムの範囲と限界を調査する.
- 非対称合成におけるキラルなRe(V) -オクソ複合体の有用性を実証する.
主な方法:
- キラルシアノビス (((オクサゾリン)) (CNbox) 結合レニウム-オクソ複合体, (CNbox) Re (((O) Cl2 (((OPPh3) の合成と特徴づけ.
- N-フォスフィニルイミンのエナンチオセレクティブ水酸化反応条件の最適化.
- アロマティック,サイクル,ヘテロアロマティック,アルファ-イミノエステル,アルファ,ベータ不飽和イミンなど,多様なイミン基板を用いた触媒性能の評価.
主要な成果:
- キラルなRe(V) -オクソ複合体は,空気と水分に耐える条件下で,N-フォスフィニルイミンのエナチオセレクティブ水酸化を効果的に触媒化する.
- 様々なアロマティック,サイクル,ヘテロアロマティック,アルファ-イミノエステル,アルファ,ベータ不飽和イミンを含む幅広い基板の範囲が達成されました.
- 試験された基板の範囲全体で,還元剤に対して良好から優れたエナンチオセレクティビティが得られた.
結論:
- 開発されたキラルRe(V) -オクソ触媒は,価値あるキラルアミンの前駆物の非対称合成のための効率的で堅固な方法を提供します.
- 触媒の空気と水分に耐える性質は,実験手順を簡素化し,その適用性を拡大します.
- この研究は,特にN-フォスフィニルイミン基板に対する,エナンチオセレクティブ水酸化反応のツールボックスを拡張します.
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