イリジウムビス (((ホスフィナイト) p-XPCPのピンチャー複合体:アルケンの転移脱水化のための非常に活性な触媒
Inigo Göttker-Schnetmann1, Peter White, Maurice Brookhart
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3290, USA.
Journal of the American Chemical Society
|February 12, 2004
まとめ
新しいイリジウムピンサー複合体は,タート-ブチルエチレンを使用して,サイクロオクタンからサイクロオクテンへの転送脱水化を触媒化する. これらの触媒は,高い活性と高回転率を示し,効率的な化学変換の可能性を示しています.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- 持続可能な化学
背景:
- イリジウムピンサー複合体は,有機合成における貴重な触媒である.
- 移転脱水化は,オレフィンとアルケンの生成のための重要な反応です.
研究 の 目的:
- 新規のbis ((phosphinite) イリジウムピンサー複合体を合成し,特徴づけること.
- サイクロオクタンの転移脱水化におけるこれらの複合体の触媒的活性を評価する.
主な方法:
- ビス (((フォスフィニット) p-XPCPIrHClの一連のピンサー複合体の合成.
- 200°Cのサイクルオクタン/テート-ブチレチレン混合物における触媒試験
- ターンオーバー数 (TONs) とターンオーバー周波数 (TOFs) を用いた触媒性能の分析.
主要な成果:
- 合成されたイリジウム複合体は前例のない触媒活性を示した.
- 高いターンオーバー数 (1400-2200) とターンオーバー周波数 (1.6-2.4 s−1) が達成されました.
- サイクロオクタンからサイクロオクテンへの効率的な変換は,水素受容体として tert-butylethylene で観察されました.
結論:
- 新しいbis ((phosphinite) イリジウムピンサー複合体は,移転脱水酸化のための非常に効果的な触媒です.
- これらの発見は,オレフィン生産のためのより効率的な触媒システムの開発への道を開きます.
関連する概念動画
Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
Leveling Effect and Non-Aqueous Acid-Base Solutions
This lesson defines the leveling effect in acidic and basic solutions and its role in aqueous and non-aqueous solutions. It is essential to understand the competing nature of various species in a chemical system.
The Leveling Effect of a Solvent
A generic acid (HA) reacts with the generic base (B-) to yield the corresponding conjugate base (A-) and conjugate acid (HB):
The Leveling Effect of a Solvent
A generic acid (HA) reacts with the generic base (B-) to yield the corresponding conjugate base (A-) and conjugate acid (HB):
Carboxylic Acids to Acid Chlorides
Carboxylic acids react with SOCl2 or PCl5 to form acid chlorides. Amongst the carboxylic acid derivatives, acid chlorides are the most reactive and synthetically important derivatives. They are useful reagents for Friedel–Crafts acylation of some aromatic compounds.
Photochemical Electrocyclic Reactions: Stereochemistry
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
Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
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...
Pericyclic Reactions: Introduction
Pericyclic reactions are organic reactions that occur via a concerted mechanism without generating any intermediates. The reactions proceed through the movement of electrons in a closed loop to form a cyclic transition state, where rearrangement of the σ and π bonds yields specific products.
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic rearrangements are...
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic rearrangements are...
![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
![[(DPEPhos)(bcp)Cu]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)
