周期性1,3-二極体または非周期性ホスフォニウムイリド "モントリオール人"の電子表記
Elizabeth H Krenske1, K N Houk, Bruce A Arndtsen
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.
Journal of the American Chemical Society
|July 12, 2008
まとめ
ミュンクノーンから派生した新しい1,3-二極反応剤は,リンと酸素の相互作用を特徴としています. 計算による研究は,この相互作用とサイクル添加の障壁に対する置換効果を明らかにしています.
科学分野:
- コンピューティング・ケミストリー
- 有機化学 オーガニック・ケミストリー
- 量子化学とは,量子化学である.
背景:
- ミュンクノネスと同様の新種の1,3-二極反応剤が開発されましたが,カルボニル基を代替するリン酸 (PR3) ユニットがあります.
- これらの新種の反応剤の構造的および電子的性質を理解することは,それらの反応性を予測するために極めて重要です.
研究 の 目的:
- 密度関数理論 (DFT) とab initio方法を使用して,これらの新しい1,3-二極反応剤の構造特性を計算的に調査する.
- 主要なP...O相互作用と反応剤のエネルギープロファイルに対する様々なリン置換剤の影響を分析する.
主な方法:
- 密度関数理論 (DFT) と初期量子化学計算を用いた.
- 協調的なサイクル添加のための幾何学,相互作用距離,および反応障壁が計算されました.
主要な成果:
- 元の反応剤 (PR3 = PH3) は,非平面的,弱いケラ化のアシラミノ-フォスフォニウムイライドとして存在し,有意なP...O相互作用があります.
- 電子を取り除くリン置換剤はP...O相互作用を強化し,より kovalent bond を好むが,電子を寄付するグループはそれを弱める.
- サイクル添加障壁は,P...O相互作用の強さと,移行状態の幾何学を達成するために必要なエネルギーと相関する.
結論:
- これらのを含有する1,3-二極反応剤の構造的および電子的性質は,原子の置換物によって調節可能である.
- サイクロアディションバリアの計算による予測は,実験的観測と一致し,理論的アプローチを検証する.
関連する概念動画
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