ニッケルメタラフォトレドックス触媒における酸化添加過渡状態の探査 内分子C動態同位体効果を用いて
Chetan Joshi1, Julia R Dorsheimer2, Victor O Nyagilo1
1Department of Chemistry, Binghamton University, Binghamton, New York 13902, United States.
Journal of the American Chemical Society
|July 1, 2025
まとめ
ニッケル・フォトレドックス触媒は軽度のC−CとC−X結合を形成する. 内分子C運動同位体効果 (KIEs) は,酸化添加におけるニッケル種を明らかにし,C2−C3クロスカップリングおよびアミンアリレーション反応の触媒サイクルを明らかにする.
科学分野:
- 有機金属化学
- カタリシス
- フォトレドックス触媒
背景:
- フォトレドックス法と組み合わせたニッケル触媒は,C-CとC-X結合形成のための穏やかな条件を提供します.
- 酸化添加段階におけるニッケル種を理解することは,反応メカニズムを明らかにするために極めて重要です.
- キネティック・イソトープ効果 (KIE) とDFT分析は,金属の酸化状態とリガンド環境に関する定量的な洞察を提供します.
研究 の 目的:
- 2つの異なるニッケルメタルフォトレドックス触媒反応における酸化添加ステップを調査する.
- 活性ニッケル種と,そのリガンド環境を触媒処理中に決定する.
- C ((sp2) -C ((sp3) のクロスカップリングとアミンアリレーションの操作的触媒サイクルを解明する.
主な方法:
- 分子内同位体効果 (KIE) の適用
- 密度関数理論 (DFT) を用いた計算分析.
- ニッケル触媒 C ((sp2) -C ((sp3) のクロスカップリングおよびアミンアリレーション反応の評価.
主要な成果:
- NiCl2 ((dtbbpy) ((H2O) 4が誘導するN-メチル選択的アリレーションでは,Ni(I) 複合体は酸化添加における可能性の高い種であり,Ni(0) 機構も確認されている.
- Ni(THMD) 2が触媒化した除染アリレーションでは,アニオン性Ni(I) 複合体が酸化添加に関与し,塩化物添加物による速度加速を説明する.
- 内分子C KIEは,ニッケルメタルフォトレドックス触媒におけるメカニズムの問題を効果的に探求する.
結論:
- この研究は,2つの異なる触媒システムにおける酸化添加に関与する主要なニッケル種を成功裏に特定した.
- この発見は,ニッケルメタルフォトレドックス触媒反応のより深いメカニズム的な理解を提供します.
- 内分子C KIEは,この分野における力学的な調査のための強力なツールとして実証されています.
関連する概念動画
Catalysis
27.6K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.6K
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
6.1K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
6.1K
Cycloaddition Reactions: MO Requirements for Photochemical Activation
2.2K
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
2.2K
Photochemical Electrocyclic Reactions: Stereochemistry
1.9K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.9K
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
10.9K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
10.9K
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
8.2K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
8.2K

![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)