Oxygen-mediated Polymerization Initiated by Oltipraz-derived Thiones
Scott R Zavada1, Joseph C Furgal2, Nathan D Wood2
1Macromolecular Science and Engineering Program, University of Michigan, Ann Arbor, MI 48109-2136, USA.
Journal of Polymer Science. Part A, Polymer Chemistry
|September 27, 2017
Summary
This study explores using a pyrrolopyrazine-thione as an initiator for radical polymerization. While it generates radicals, side reactions limit polymerization success due to complex chemical interactions.
Area of Science:
- Polymer Chemistry
- Organic Synthesis
Background:
- Oltipraz derivatives are known chemopreventive agents.
- Pyrrolopyrazine-thiones can generate radicals via redox cycling with thiols and oxygen.
- Radical-mediated thiol-ene polymerization is a valuable synthetic tool.
Purpose of the Study:
- To investigate the use of an in situ generated pyrrolopyrazine-thione as an initiator for radical-mediated thiol-ene polymerization.
- To understand the factors influencing the efficiency of this polymerization system.
Main Methods:
- In situ generation of pyrrolopyrazine-thione from a precursor.
- Initiation of radical-mediated thiol-ene polymerization.
- Analysis of reaction extents and identification of side reactions.
Main Results:
- Pyrrolopyrazine-thione successfully generated radicals in the presence of thiols and oxygen.
- Achieved reaction extents were limited by undesired side reactions that quenched radical production.
- Complex interactions between the initiator, precursor, oxygen, and thiols were identified as critical factors.
Conclusions:
- Pyrrolopyrazine-thione shows potential as an oxygen-mediated polymerization initiator.
- Optimization is needed to overcome side reactions and enhance polymerization efficiency.
- Understanding the intricate reaction network is key to successful application.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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