Radical Cations of Phenoxazine and Dihydrophenazine Photoredox Catalysts and Their Role as Deactivators in Organocatalyzed Atom Transfer Radical Polymerization.
Radical Cations of Phenoxazine and Dihydrophenazine Photoredox Catalysts and Their Role as Deactivators in Organocatalyzed Atom Transfer Radical Polymerization.
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DOI：
10.1021/acs.macromol.1c00640
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发表时间：
2021-05-25
期刊：
影响因子：
5.5
通讯作者：
Miyake GM
中科院分区：
文献类型：
--
作者：
Corbin DA;McCarthy BG;van de Lindt Z;Miyake GM
合成了用于有机催化原子转移自由基聚合（O-ATRP）的光氧化还原催化剂的自由基阳离子，并对其失活机理进行了研究。这些化合物的稳定性和反应性进行了研究，在两种溶剂中，N，N-二甲基乙酰胺和乙酸乙酯，以确定可能的副反应，O-ATRP和调查这些自由基阳离子的能力，使烷基自由基失活。一些其他因素，可能会影响O-ATRP的失活也进行了探讨，如离子配对与自由基阳离子，自由基阳离子氧化电位，和卤化物氧化电位。最终，这些研究使自由基阳离子作为O-ATRP过程中的试剂，以证明随着自由基阳离子浓度的增加，聚合控制的改善。在丙烯酸酯的聚合中，这种方法能够实现上级分子量控制，聚合物分散度从1.90降低到1.44，并且引发剂效率从78%增加到102%。这项工作强调了理解O-ATRP的机理和副反应的重要性，以及催化剂自由基阳离子对成功O-ATRP的重要性。
Radical cations of photoredox catalysts used in organocatalyzed atom transfer radical polymerization (O-ATRP) have been synthesized and investigated to gain insight into deactivation in O-ATRP. The stability and reactivity of these compounds were studied in two solvents, N,N-dimethylacetamide and ethyl acetate, to identify possible side reactions in O-ATRP and to investigate the ability of these radical cations to deactivate alkyl radicals. A number of other factors that could influence deactivation in O-ATRP were also probed, such as ion pairing with the radical cations, radical cation oxidation potential, and halide oxidation potential. Ultimately, these studies enabled radical cations to be employed as reagents during O-ATRP to demonstrate improvements in polymerization control with increasing radical cation concentrations. In the polymerization of acrylates, this approach enabled superior molecular weight control, a decrease in polymer dispersity from 1.90 to 1.44, and an increase in initiator efficiency from 78 to 102%. This work highlights the importance of understanding the mechanism and side reactions of O-ATRP, as well as the importance of catalyst radical cations for successful O-ATRP.
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影响因子：
4.6
作者：
Corbin DA;McCarthy BG;Miyake GM
通讯作者：
Miyake GM
影响因子：
15
作者：
Flory, PJ
通讯作者：
Flory, PJ
影响因子：
16.6
作者：
Buss, Bonnie L.;Lim, Chern-Hooi;Miyake, Garret M.
通讯作者：
Miyake, Garret M.
影响因子：
8.4
作者：
Lewis-Borrell L;Sneha M;Bhattacherjee A;Clark IP;Orr-Ewing AJ
通讯作者：
Orr-Ewing AJ
影响因子：
15
作者：
Chen, Dian-Feng;Boyle, Bret M.;Miyake, Garret M.
通讯作者：
Miyake, Garret M.