Oxygen-mediated Polymerization Initiated by Oltipraz-derived Thiones.
Oxygen-mediated Polymerization Initiated by Oltipraz-derived Thiones.
复制标题
由吡啶硫酮衍生的硫酮引发的氧介导聚合。
DOI：
10.1002/pola.28507
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
Scott,TimothyF
中科院分区：
文献类型：
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作者：
Zavada,ScottR;Furgal,JosephC;Wood,NathanD;Scott,TimothyF
吡咯并吡嗪硫酮衍生自吡咯并吡嗪硫酮，这是一种已被研究作为化学预防剂的化合物，在硫醇和氧气存在下通过氧化还原循环提供自由基，这一属性表明其适合作为氧介导聚合的引发剂。在这里，我们探索了利用这种由前体原位生成的吡咯并吡嗪硫酮作为自由基介导的硫醇-烯聚合的引发剂。虽然吡咯并吡嗪硫酮被证明能够在大气氧和硫醇基团存在的情况下产生自由基，但由于存在不需要的副反应，可实现的反应程度低于预期，副反应会猝灭自由基的产生，随后抑制聚合。此外，我们发现吡咯并吡嗪硫酮、其前体、氧和硫醇基团之间的复杂相互作用决定了猝灭反应是否比有利于聚合的反应占主导地位。 © 2016 Wiley periodicals, Inc. J. Polym。科学，A 部分：聚合物。化学.2017,55, 1373–1382
A pyrrolopyrazine‐thione derived from oltipraz, a compound that has been investigated as a chemopreventive agent, affords radicals in the presence of thiols and oxygen via a redox cycle, an attribute that suggests its suitability as an initiator for oxygen‐mediated polymerization. Here, we explore the utilization of this pyrrolopyrazine‐thione, generated in situ from a precursor, as an initiator for the radical‐mediated thiol–ene polymerization. While the pyrrolopyrazine‐thione was shown to be capable of generating radicals in the presence of atmospheric oxygen and thiol groups, the reaction extents achievable were lower than desired owing to the presence of unwanted side reactions that would quench radical production and, subsequently, suppress polymerization. Moreover, we found that complex interactions between the pyrrolopyrazine‐thione, its precursor, oxygen, and thiol groups determine whether or not the quenching reaction dominates over those favorable to polymerization. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2017,55, 1373–1382