置換されたフェニルニトロニウムイオンの電子構造に対するメタ電子ドナー群の作用
Arthur H Winter1, Daniel E Falvey, Christopher J Cramer
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742-2021, USA.
Journal of the American Chemical Society
|August 5, 2004
まとめ
電子ドナー置換剤は,フェニルニートレニウムイオンの三重体状態を基底状態にすることができます. この研究は,置換効果に基づいて, n,pi と pi,pi の2つの異なる低エネルギー三重状態を特定しています.
科学分野:
- 計算化学はコンピュータ化学である.
- 量子化学は量子化学である
- オーガニック化学 オーガニック化学
背景:
- フェニルニートレニウムイオンは,反応性中間物質である.
- 電子状態を理解することは,反応機構にとって極めて重要です.
研究 の 目的:
- メタ置換されたフェニルニートレニウムイオンにおけるシングレット・トリプレットのエネルギーギャップに対する置換効果を調査する.
- 低い三重状態の電子構造を特徴づけるために.
主な方法:
- 密度関数理論 (DFT) は,UB3LYP/6-31G (((d,p)) レベルの理論を使用しています.
- 均衡幾何学,コーン・シャム軌道分布,マルリケンのスピン密度の分析.
主要な成果:
- 強烈に電子を寄付する置換物質はトリプル状態を安定させ,潜在的にそれを基本状態にします.
- n,pi と pi,pi の2つの異なる低エネルギー三重状態が特定されました.
- n,piトリエット (単純および電子取り除く/弱寄与置換物) は,コプラナー1つと,オートゴーナル1つの単体で占有される分子軌道を有する.
- pi,pi トリプルツ (強いメタドナー) は,フェニル環に直角な分子軌道の両方を単独で占有しています.
結論:
- 置換効果は,フェニルニートレニウムイオンの基底状態に大きな影響を与える.
- 三重ニトロニウムイオンの電子構造は,n,pi,pi,piタイプに分類することができます.
- これらの発見は,アリルニートレニウムイオンの電子特性と反応性についての洞察を提供します.
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