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2,3-ジクロル-5,6-ディシアノ-1,4-ベンゾキノンによる酸化C-H結合機能化反応の予測モデル

Cristian A Morales-Rivera¹, Paul E Floreancig¹, Peng Liu¹

¹Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States.

Journal of the American Chemical Society

|November 15, 2017

まとめ

2,3-ジクロル-5,6-ディシアノ-1,4-ベンゾキノン (DDQ) は,ヒドリド移転経由でC-H結合の機能化を促進する. 計算研究により,反応性はカルボケーションの安定性と電荷移転に依存し,様々な基板の予測モデル化が可能になった.

科学分野:

有機化学
コンピュータ化学
反応メカニズム

背景:

2,3-ディクロロ-5,6-ディシアノ-1,4-ベンゾキノン (DDQ) は,C-H機能化の強力な反応剤である.
ベンジル系およびアリル系C-H結合のDDQ媒介による酸化分裂は,新しい結合形成を可能にします.

研究の目的:

DDQ媒介による酸化C-H分裂反応のメカニズムを解明する.
代用剤が反応経路と結果に及ぼす影響を調査する.
DDQによるC-H機能化の予測モデルを開発する.

主な方法:

密度関数理論 (DFT) の計算を使用した.
電荷伝送複合体と移行状態の分析
カーボケーション中間安定性と二次軌道相互作用の調査.

主要な成果:

DDQ反応は,電荷移転複合体内の水素移転を経由して進行する.
反応性は,カーボケーションの安定性と移行状態の電荷移転によって制御される.
二次軌道相互作用は,特定の基板のケースで役割を果たします.
反応性の予測のために線形自由エネルギー関係が確立された.

結論:

この研究は,DDQ媒介のC-H機能化に関する詳細なメカニズム的洞察を提供します.
代替剤の反応性への影響は,電子特性と中間安定性によって説明される.
開発されたモデルは,様々なC−H結合型の反応性を正確に予測します.

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