ヴィニルフォスフィラン-フォスフォレンの再配置:ペリサイクル [1,3]-シグマトロピクシフトか否か?
Rosa E Bulo1, Andreas W Ehlers, Stefan Grimme
1Department of Chemistry, FEW, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
Journal of the American Chemical Society
|November 15, 2002
まとめ
密度関数理論によると,2-ビニルフォスフィランは[1,3]-シグマトロピクシフトを経て,3-フォスフォレンを形成し,炭化水素類似体よりもエネルギーバリアが低い. Cr ((CO) ((5) との複合は,これらの再配列をさらに安定させる.
科学分野:
- 有機金属化学 有機金属化学
- コンピューティング・ケミストリー
- 有機反応のメカニズム
背景:
- [1,3]-シグマトロピクシフトは,有機化学における基本的な反応である.
- リンを含むヘテロサイクルは,炭素同類と比較してユニークな反応性を提供します.
- 金属の複合化により,反応経路とエネルギーが大きく変化します.
研究 の 目的:
- 2-ビニルフォスフィランの[1,3]-シグマトロピク再配置を調査し,ビニルサイクロプロパンシステムと比較する.
- 再配置の障壁とメカニズムに対するCr (Cr) ・CO (CO) ・5) 複合体の効果を明らかにする.
- これらの変換のステレオ化学的結果とエネルギープロフィールを計算的方法を使用して分析する.
主な方法:
- 密度関数理論 (DFT) の計算を用いて,潜在エネルギー表面をマッピングした.
- 移行状態と反応障壁は,さまざまな経路で特定されました.
- マルチリファレンスの方法を使用して,DFT由来の活性化エネルギーを検証しました.
主要な成果:
- 2-ビニルフォスフィランは,ビニルサイクロプロパンよりも低いバリアを持つ協調した環循環 [1,3]-シグマトロピクシフトを経由して,3-フォスフォレンに再編成されます.
- Cr (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr)
- リンでのエピメリゼーションは,ダイラジカルのようなリング開閉式リング閉式機構を通じて発生します.
- P-フェニルグループの存在は,好ましい経路に影響を与え,実験観察と一致します.
結論:
- 2 - ビニルフォスフィランの [1,3] - シグマトロピク再配置は,ビニルサイクロプロパンのダイラジカルのようなメカニズムとは異なるペリサイクリックなプロセスです.
- Cr (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr) CO (Cr (Cr) CO (Cr) (Cr) (Cr)
- コンピューティングによる研究は,これらの有機リンリアレンジメントのメカニズムとステレオ選択性に関する貴重な洞察を提供します.
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