ハモンド定理のミラーリングは,2つの熱力学的に相互接続されたシーケンス的なステレオセレクティブプロセスを通して,リン化合物のエナティオメア濃縮を可能にします
Kamalraj V Rajendran1, Kirill V Nikitin1, Declan G Gilheany1
1Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland.
Journal of the American Chemical Society
|July 18, 2015
まとめ
この研究は,リン化合物の運動解像度法を明らかにしています. ダイアステロエーマーアルコキシホスフォニウム塩は分解時に自己濃縮され,最終製品のエナティオメア過剰を最大97%まで増加させます.
科学分野:
- 有機化学
- ステレオ化学
- スペクトロスコーピー
背景:
- 三次フォスフィンとフォスフィン酸化物は有機合成において極めて重要です.
- リン化学におけるステレオ選択性を制御することは困難です.
- ダイナミック解像度は高いエナティオメア純度への道筋を提供します.
研究 の 目的:
- 三次フォスフィンとフォスフィン酸化物のダイナミック解像度を調査する.
- 中間物質の形成と分解におけるステレオ選択性を決定するステップを理解する.
- リン製品における高エナティオメール過剰 (ee) を達成するための方法を開発する.
主な方法:
- 核磁気共振 (NMR) スペクトロスコーピー,特に (31) P NMRは,反応を監視するために使用されました.
- ディアステロエーマーアルコキシホスフォニウム塩 (DAPS) を合成して分析した.
- リチウムトライセックブチルボロヒドリド (L-セレクトリド) を用いた還元捕獲実験は,さまざまな時間点で行われました.
主要な成果:
- ステレオ選択性はDAPS形成時に確立され,その後のエナティオメア過剰を制限します.
- (31) P NMRモニタリングは,DAPS分解の過程で自発的なダイアステレオメアの自己濃縮を明らかにした.
- フォスフィン産物のエナチオメリック過剰が徐々に増加し,反応時間が長くなることが観察されました.
- 最終的なリン製品では最高97%のEEが達成された.
結論:
- DAPSの分解は,マイナー・ダイアステロエーマーに好意的なダイアステロエーマー自己濃縮を示します.
- ハモンド定理は DAPSの形成と分解の動態の両方を支配する.
- この運動解像度の強化は,高度にエナチオメリックに富んだリン化合物への効果的な経路を提供します.
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