![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
Visible Light Catalyzed Step-Growth Polymerization through Mizoroki-Heck Coupling Reaction
Liting He1, Chunbo Jia1, Yunjia Zhang1
1The State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200433, China.
Macromolecular Rapid Communications
|February 6, 2020
Summary
Visible light accelerates palladium-catalyzed Mizoroki-Heck coupling polymerization. This process enhances polymerization rates and polymer molecular weights, offering a novel, sensitizer-free approach for polymer synthesis.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
- Photochemistry
Background:
- Palladium-catalyzed Mizoroki-Heck coupling is a vital reaction in organic synthesis.
- Visible light photoredox catalysis has emerged as a powerful tool in organic chemistry.
- Step-growth polymerization is crucial for creating high molecular weight polymers.
Purpose of the Study:
- To investigate the effect of visible light on palladium-catalyzed Mizoroki-Heck coupling for polymer synthesis.
- To elucidate the mechanism by which light influences the reaction kinetics.
- To demonstrate the application of this light-driven process in step-growth polymerization.
Main Methods:
- Visible light irradiation (blue light, λ = 465 nm) of Mizoroki-Heck coupling reaction.
- Kinetic studies to compare polymerization rates under light and in the dark.
- Mechanistic investigation using Fluorine-19 Nuclear Magnetic Resonance (19 F NMR) spectroscopy.
Main Results:
- Polymerization rate is significantly faster under visible light irradiation compared to dark conditions.
- Higher molecular weight polymer products are obtained when using light.
- 19 F NMR studies indicate light activates the oxidative addition step, accelerating intermediate formation.
Conclusions:
- Visible light enhances the rate and efficiency of palladium-catalyzed Mizoroki-Heck polymerization.
- A novel mechanism for light's effect on Mizoroki-Heck coupling, without a sensitizer, has been revealed.
- This work presents the first application of light-driven Mizoroki-Heck coupling in step-growth polymerization.
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