オレフィンメタテシスの基本的なステップ:ニッケルカルベンのサイクル添加によるニッケルサイクロブータン
Samantha K Cormier1, Marco Foscato2, Michael J Ferguson3
1Centre for Catalysis Research & Innovation and Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
Journal of the American Chemical Society
|July 7, 2025
まとめ
この研究は,ニッケル複合体がオレフィン転移の重要なサイクル添加ステップを実行できることを示しています. この発見は,持続可能な"列目移行金属触媒"の開発に不可欠な証拠を提供します.
科学分野:
- 有機金属化学
- 持続可能な触媒
背景:
- プラチナ群の金属はオレフィン転化とサイクロプロパネーションの触媒を支配する.
- 第"列の移行金属は持続可能な代替手段を提供しているが,重要な反応段階の証拠は欠けている.
研究 の 目的:
- ニッケル触媒化オレフィンメタテシスのサイクル添加ステップの化学的可行性を証明する.
- オレフィンメタテシスを達成するためのニッケル複合体の設計パラメータを確立する.
主な方法:
- Ni ((PP) ((=CPh2) 複合体の合成と特徴付け
- 複合体のスタイレンとフェニルビニル硫黄 (PVS) との反応
- NMR分析とX線結晶学でニケラサイクロブタン中間物質を観察する.
- 反応経路とエネルギーバリアを分析するための計算研究.
主要な成果:
- Ni ((PP) ((=CPh2) 複合体はスタイレンとPVSと反応し,ニケラサイクロブタン (NiCB) の中間物質を示すβ-H除去産物を生成した.
- PVSシステムでは,NMRとX線結晶学によって,NiCB中間物質が直接観察されました.
- 計算により,サイクル逆転に対するエネルギーバリアの減少がメタテシスにとって重要であることが明らかになった.
結論:
- ニッケル複合体は,オレフィン転化の前提条件であるサイクル添加ステップに成功します.
- この研究は,オレフィン転化触媒の有効な金属としてのニッケルを検証している.
- 効率的なニッケルベースのメタテシス触媒の開発のための主要な設計原則が確立されました.
さらに関連する動画
関連する概念動画
Olefin Metathesis Polymerization: Overview
2.2K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
2.2K
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
2.0K
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
2.0K
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
Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
2.7K
Ring-opening metathesis polymerization or ROMP involves strained cycloalkenes as starting materials. The mechanism of ROMP proceeds by reacting cycloalkene with Grubbs catalyst to give metallacyclobutane intermediate which undergoes a ring-opening reaction to form new carbene. The new carbene reacts with another molecule of cycloalkene. Repetition of these steps leads to the formation of an unsaturated open-chain polymer product. All these steps are reversible, however, relieving the ring...
2.7K
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
2.0K
The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.
2.0K
Cycloaddition Reactions: Overview
2.8K
Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
2.8K


