オープンシェルシングレットフェニロキセニウムイオンの直接検出:原子中心のダイラジカルが電愛体として反応する

Lili Du¹, Yunfan Qiu², Xin Lan¹

¹Department of Chemistry, The University of Hong Kong , Pokfulam Road, Hong Kong, People's Republic of China.

Journal of the American Chemical Society

|September 26, 2017

まとめ

この研究は,前述のダイラジカル反応性仮定に異議を唱え,核愛的な攻撃を受ける強力な電愛体である開いた殻のシングレットフェニロセニウムイオンを生成する新しい光前駆体を示しています.

科学分野:

写真化学
有機化学
物理化学

背景:

フェニロキセニウムイオンは,有機反応における重要な中間物質である.
オープンシェルのシングレットディラジカルの反応性を理解することは,化学合成に極めて重要です.
以前の研究ではシングレット・ディラジカルが核愛性の攻撃を受ける可能性があると示唆されていた.

研究の目的:

新しいフェニロキセニウムイオン光前駆体の光物理学と光化学を調査する.
光分解中に形成された一時的な中間物質を特徴付ける.
オープンシェルの単体フェニロキセニウムイオンの反応性を決定する.

主な方法:

レーザーフラッシュ光分解 (フェムト秒からミリ秒までの時間スケール)
捕獲調査
製品分析
計算による調査
時間の解像度による共振ラーマン光譜法

主要な成果:

新しい光前駆体である4-メトキシフェノキシピリジニウムテトラフローロボラートが合成され,研究された.
興奮状態は, ~2 psで開いた殻の単離フェニロキセニウムイオン (1A2) を形成する.
この開いた殻のイオンは強力な電極性であり,溶媒の捕獲を受け,リッターの中間物質を形成します.
オープンシェルのシングレットダイラジカルが電愛体として反応する直接のスペクトル観測が達成された.

結論:

シングレットダイラジカル反応性には再評価が必要で,強力な電愛体として作用する.
単体で占有された分子軌道に対する核愛的攻撃は,開いた殻の単体ダイラディカルに可能である.
この研究は,原子中心のオープンシェルシングレットダイラディカルの電愛性行為の直接的な証拠を提供します.

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