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Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
アリル基のフォスファニレーションにおける軸性キラリティの記憶
Achim Bruch1, Andrea Ambrosius, Roland Fröhlich
1Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany.
Journal of the American Chemical Society
|July 30, 2010
まとめ
トリメチルスタニルディフェニルフォスファンは,アリル基を効率的にフォスファニレートし,軸性キラリティを維持します. この反応は,非対称な触媒の研究に価値のあるキラル・フォスファンおよび誘導体を生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 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
背景:
- アリルラジカルは,有機合成における重要な中間物質である.
- キラル・フォスファンは,非対称な触媒における重要なリガンドである.
- キラルフォスファンを合成するための効率的な方法の開発は極めて重要です.
研究 の 目的:
- アリル基のフォスファニル化速度の定数を測定する.
- フォスファニレーション反応のステレオ化学的結果を調査する.
- キラルリン酸塩およびその誘導体の合成を調査する.
主な方法:
- トリメチルスタニルディフェニルフォスファン (Me(3) SnPPh(2) を使用してフォスファニレーションの速度常数の測定.
- 軸性キラルオハロアニリドから派生したアリル基を捕まえる.
- 分析のために,ホスファンの酸化物をホスファンの酸化物または硫化物に酸化する.
- 二重フォスファニル化と,その後の酸化/硫化.
- ダイアステロエーマーの化学変異性トラッピング.
主要な成果:
- フォスファニレーションの速度定数は,およそ 9 x 10 ((8) M ((-1) s ((-1)) と決定されました.
- アリルラジカルのフォスファニル化中に軸性キラリティは完全に保持されました.
- 混合ディフォスファン酸化硫化物のエナントイオマーを合成した.
- ダイアステロエーマーの化学分岐捕獲は,反応条件に基づいて異なる製品形成をもたらしました.
結論:
- トリメチルスタニルディフェニルフォスファンは,アリル基のフォスファニル化のための効果的な反応剤で,高いステレオ化学的忠誠度を持っています.
- 開発された方法は,キラルトリアリルホスファン,酸化物,硫化物の合成を可能にします.
- これらのキラル化合物は,非対称な触媒のリガンドとしての可能性を秘めています.
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