RUI: Synthesis of Macrocyclic Polymers Using Radical Trap Assisted-Intramolecular Atom Transfer Radical Coupling

在这个由化学系高分子、超分子和纳米化学计划资助的项目中，巴克内尔大学的Eric Tillman将设计合成大环聚合物的路线，这种聚合物具有一系列不同于其线性类似物的性质，并在使用聚合物的不同领域提供潜在优势。这一建议的重点是在二卤代线性前体的端到端原子转移自由基偶联反应中添加一个自由基陷阱，如亚硝基，从而创造了一种情况，即卤化链末端不再需要同时活化才能进行环关闭。这条合成路线将应用于合成各种大环结构，从环状两嵌段共聚物、生色团功能化的环状聚合物，甚至复杂的多环结构。作为这项研究的更广泛影响，本科生和硕士研究生将在聚合物材料的合成和表征方面获得宝贵的培训。聚合物是长链有机分子，存在于日常生活的许多方面，使用塑料，包括食品包装、汽车和航空航天运输的结构材料，以及轻型电子设备。环状聚合物提供了一系列性质，这些性质通常与从中衍生出来的线性聚合物有很大不同，但众所周知很难合成。环状聚合物可能在电子材料和药物输送载体等方面具有潜在的应用价值。这项研究致力于开发一种新的、直接的方法来制备环状聚合物，并将该策略应用于制备具有复杂环状结构的聚合物。

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Eric Tillman of Bucknell University will devise synthetic routes leading to macrocyclic polymers, which posses a set of properties distinct from their linear analogs and offer potential advantages in diverse areas in which polymers are used. The focus of this proposal is the addition of a radical trap, such as a nitroso group, to an end-to-end atom transfer radical coupling reaction of a dihalogenated linear precursor, creating a scenario where the halogenated chain ends no longer require simultaneous activation to undergo ring closure. This synthetic route will be applied to the synthesis of a variety of macrocyclic architectures, from cyclic diblock copolymers, chromophore-functionalized cyclic polymers, and even complex multicyclic structures. As a broader impact of the research, undergraduate and Masters-level students will gain valuable training in both synthesis and characterization of polymeric materials.Polymers are long chain organic molecules and are found in many facets of everyday life that utilize plastics, including food packaging, structural materials for automotive and aerospace transportation, and lightweight electronic devices. Cyclic polymers offer a set of properties that often differ substantially from the linear polymers from which they are derived, yet are notoriously difficult to synthesize. Cyclic polymers may be potentially useful in a variety of applications, such as electronic materials and drug delivery vehicles. This research focuses on both developing a new, straightforward route to preparing cyclic polymers and applying this strategy to prepare polymers displaying complex cyclic architectures.