First report on the sequential, visible light‐initiated, single unit monomer insertion (SUMI) of N,N‐dimethylacrylamide (DMAm) into the reversible addition fragmentation chain transfer (RAFT) agent, 4‐((((2‐carboxyethyl)thio)carbonothioyl)thio)‐4‐cyanopentanoic acid (CTA₁), in aqueous solution is provided. The specificity for SUMI over formation of higher oligomers and/or RAFT agent‐derived by‐products is higher for longer irradiation wavelengths. Red light provides the cleanest product (selective SUMI), showing a linear pseudo‐first order kinetic profile to high (>80%) conversion, but also the slowest reaction rate. Blue light provides a relatively rapid reaction, but also gives some by‐products (<2%) and the kinetic profile displays a conversion plateau at >65% conversion. Higher specificity with red light is attributed to CTA₁ absorbing at longer wavelengths than the SUMI product, which allows selective excitation of CTA₁. The use of a higher reaction temperature (65 °C vs ambient) results in a higher reaction rate and a reduction in oligomer formation.

中文翻译：

---

光诱导的RAFT单体在水溶液中的单体插入—趋向于序列控制的聚合物

关于将N，N-二甲基丙烯酰胺（DMAm）连续，可见光引发的单体单体（SUMI）顺序插入可逆加成断裂链转移（RAFT）试剂4-（（（（（2-羧乙基）硫代） ）（碳硫基）硫基）-4-氰基戊酸（CTA ₁），以水溶液形式提供。对于更长的照射波长，SUMI对形成更高的低聚物和/或RAFT试剂衍生的副产物的特异性更高。红光提供最干净的产物（选择性SUMI），显示出高（> 80％）转化率的线性拟一级动力学曲线，但反应速度最慢。蓝光提供了一个相对较快的反应，但也产生了一些副产物（<2％），动力学曲线显示了> 65％转化率的转化平稳期。红光的更高特异性归因于CTA ₁吸收的波长比SUMI产品更长的波长，从而可以选择性激发CTA ₁。使用较高的反应温度（相对于环境温度为65°C）会导致较高的反应速率并减少低聚物的形成。