イリジウム・モノデンテート・フォスフォラミドイト触媒による代替ベンゾフェノンN-Hイミンの非対称な水素化
Guohua Hou1, Ran Tao, Yongkui Sun
1Department of Chemistry, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey 08854-8066, USA.
Journal of the American Chemical Society
|January 29, 2010
まとめ
この研究は,同質的非対称水素化を用いてキラルアミンを生成する新しい方法を示しています. このプロセスは,保護されていないベンゾフェノンイミンから高エナンチオセレクティブ性を持つ有価なキラルアミンを効率的に生成します.
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
- グリーン・ケミストリー (Green Chemistry)
背景:
- チラルアミンは,医薬品や微細化学薬品の重要な構成要素です.
- 非対称な水素化のための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.
研究 の 目的:
- 保護されていないベンゾフェノンN-Hイミンのための新しい均質な非対称な水素化法を開発する.
- キラルアミンの合成のための高収量およびエナチオセレクティビティを達成するために.
主な方法:
- イリジウムベースの触媒,特にIr-(S) -N-ベンジル-N-メチル-モノフォスを利用しました.
- 保護されていないベンゾフェノンのN-Hイミン (1a-r) の範囲で均質な非対称な水素化を行った.
主要な成果:
- ターゲットキラルアミン (2a-r) に対して高収量 (80-96%) を達成した.
- 優れたエナチオ選択性 (98% eeまで) が得られ,特にオーソ置換基板の場合はそうである.
- 18のさまざまな例でメソッドを成功裏に実証しました.
結論:
- 開発されたIr触媒化水素化は,キラルアミンを合成する効果的な方法である.
- このプロトコルは,広く適用可能であり,特にステリカルに阻害された基板に対して,高い効率性を示しています.
関連する概念動画
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