アルファ置換のシン-アルファ,ベータ-ダイアミノ酸のダイアステレオおよびエナチオセレクティブ合成です
Anand Singh1, Jeffrey N Johnston
1Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235-1822, USA.
Journal of the American Chemical Society
|April 16, 2008
まとめ
新しい方法は,α,β-ダイアミノフェニルアラニン誘導体の高度選択的合成を達成します. キラルプロトン触媒と特定のニトロエスターは,イミンの添加物におけるステレオ化学を正確に制御することを可能にします.
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・シンセシス
- カタリシス カタリシス カタリシス
背景:
- アミノ酸誘導体のキラル合成は,医薬品にとって極めて重要です.
- ステレオ化学的に定義された分子を生成するための効率的な方法の開発は,依然として課題です.
研究 の 目的:
- イミンにアルファ-ニトロエステルを加えるための高度にダイアステロ選択的およびエナチオ選択的方法を開発する.
- アルファ,β-ダイアミノフェニルアラニン誘導体の単純な合成プロトコルを作成する.
主な方法:
- 代用されたアルファ-ニトロアリルエステルと組み合わせた二機能性キラルプロティック酸触媒を使用した.
- 添加反応における基板制御のダイアステロセレクションと,触媒制御のエナチオセレクションを研究した.
主要な成果:
- 高いダイアステロセレクション (>20:1) を達成し,基板制御を通してシンダイアステロエーマーを好む.
- アゾメチンのパイ面を区別する触媒制御による優れたエナチオセレクティブ性 (最大99%) が得られた.
- 基板の別々の事前活性化を必要としないプロトコルを実証しました.
結論:
- 開発された方法は,価値あるアルファ,β-ダイアミノフェニルアラニン誘導体への簡単で高度に選択的な経路を提供します.
- 二機能性キラル触媒は,高いダイアステレオ選択性とエナチオ選択性の両方を達成する上で重要な役割を果たします.
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