鉄触媒アルケンの基質依存二次反応 [2+2] サイクル添加反応

Lianrui Hu^1,2, Hui Chen¹

¹Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Photochemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China.

Journal of the American Chemical Society

|October 25, 2017

まとめ

鉄の触媒は,アルケンの [2+2] サイクル添加を段階的な経路で挑戦することができます. この研究は,鉄触媒における基質依存の二次反応性を明らかにし,基本的な反応機構を明らかにした.

科学分野:

有機金属化学
カタリシス
反応メカニズム

背景:

鉄触媒アルケンの [2+2] サイクル添加は,運動的に阻害された協調反応の段階的な代替案を提供します.
これらの鉄触媒化されたプロセスを支配する基本的な反応性パラダイムは,大部分が未定義のままである.

研究の目的:

鉄触媒アルケンの [2+2] サイクル添加反応における基質依存反応シナリオを解明する.
触媒サイクルにおける酸化還元活性リガンドと電子状態の役割を明確にする.

主な方法:

高レベルのCASPT2/DFTコンピューティングモデリング
鉄触媒における主要な炭素-炭素結合ステップの分析.
メタラサイクルの中間物質と還元性排出経路の調査

主要な成果:

基質依存の2つの状態の反応性シナリオは,前例のないC-Cカップリングステップで特定されました.
モノオレフィンとモノオレフィン/1,3-ダイネ基板は,異なる反応性パラダイムを示している.
レドックス活性リガンドはFe (III) /Fe (I) 還元性排出経路を促進し,Fe (II) /Fe (0) よりもアクセスしやすい.

結論:

この研究は,鉄触媒による [2+2] サイクル添加のメカニズムを明らかにし,反応性に対する基質の影響を強調した.
スピン状態の移行効率の向上は,クロスサイクル添加における反応性を高める戦略を提供します.
Ab initio マルチレファレンス方法は,複雑なオープンシェルの鉄触媒に有効です.

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