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Updated: Feb 27, 2026

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Ni-Catalyzed C-H Functionalizationの計算研究:酸化添加と急進経路の競争を制御する要因

Humair M Omer¹, Peng Liu¹

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

Journal of the American Chemical Society

|July 1, 2017

まとめ

密度関数理論 (DFT) は,ニッケル触媒によるC-H機能化メカニズムを明らかにする. 基板の性質は,反応がNi (IV) 中間物質かNi (III) 基幹経路によって進行するか,C-CとC-X結合形成を制御するかを決定する.

科学分野:

有機金属化学
コンピュータ化学
キャタリシス

背景:

ニッケル触媒はC-H機能化に不可欠です.
反応メカニズムを理解することは,触媒の効率を最適化するための鍵です.

研究の目的:

Ni-触媒化C-Hアリレーション,アルキル化,およびスルフェニル化のメカニズムを調査する.
C-CとC-X結合形成経路を制御する要因を決定する.
C−H機能化における基質制御反応性と選択性を説明する.

主な方法:

密度関数理論 (DFT) の計算を用いた.
C-H分裂のための協調メタリオン-デプロトネーション (CMD) の分析.
Ni (IV) 中間物質とNi (III) ラジカルを含む経路の評価

主要な成果:

C-H分裂は一貫してCMD経由で発生する.
その後の結合形成は,結合パートナーに依存し,低結合解離エネルギー (BDE) のステリカルに阻害された基板では,根路が優勢である.
不安定な原発の前駆体については,Ni (IV) の中間体による酸化添加/還元除去が好ましい.

結論:

Ni触媒によるC-H機能化のメカニズムは基板に依存する.
DFTの洞察は,置換剤効果,化学反応,地域選択性などの実験的観測を説明する.
この研究は,効率的なC−H機能化反応の設計のための理論的枠組みを提供する.

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