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

在这个由化学部门的大分子、超分子和纳米化学项目资助的项目中，巴克内尔大学的埃里克·蒂尔曼将设计出合成大环聚合物的路线，这种聚合物具有一系列与线性类似物不同的特性，并在聚合物使用的不同领域提供潜在的优势。本提案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，从而创造出一种卤化链末端不再需要同时激活才能进行环闭合的情况。该合成路线将应用于各种大环结构的合成，从环二嵌段共聚物，发色团功能化环聚合物，甚至复杂的多环结构。由于该研究的广泛影响，本科生和硕士生将在聚合材料的合成和表征方面获得宝贵的训练。聚合物是长链有机分子，在日常生活的许多方面都使用塑料，包括食品包装，汽车和航空航天运输的结构材料，以及轻质电子设备。环状聚合物提供了一组性质，这些性质通常与它们衍生的线性聚合物有很大的不同，但众所周知，它们很难合成。环状聚合物可能在多种应用中具有潜在的用途，例如电子材料和药物输送载体。本研究的重点是开发一种新的，直接的途径来制备环状聚合物，并应用这种策略来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.