Phan Hoa, Herng Tun Seng, Xudong Hou, Nguyen Linh Khanh, La Vinh The, Huynh Chinh Dang, Ding Jun, Wu Jishan
School of Chemistry and Life Science, Hanoi University of Science and Technology Hanoi Vietnam
Department of Materials Science and Engineering, National University of Singapore 119260 Singapore Singapore.
RSC Adv. 2024 May 24;14(24):16945-16950. doi: 10.1039/d4ra03034f. eCollection 2024 May 22.
The syntheses of high-spin organic polymers have been a daunting task due to the highly reactive nature of organic radicals, especially when they are ferromagnetically coupled. In this paper, we report our approach to obtain high-spin organic polymers, in which a reasonably stable fluorenyl radical was employed as the primary radical unit, and -triazine serves as the connector that facilitates ferromagnetic coupling between them. Initially, the diamagnetic polymer precursor was synthesized by cyclotrimerization of a cyano-monomer. Subsequently, the high-spin polymers were obtained by oxidizing corresponding anionic polymers using O (6) or I (7). The temperature-dependent magnetic moments, and field-dependent magnetization data obtained from SQUID measurements revealed ferromagnetic couplings between primary radical units, with coupling = 7.5 cm and 38.6 cm. The percentages of primary unit in the radical form are 29%, and 47% for 6 and 7, respectively. Notably, this marks the first reported instance of a high-spin fluorenyl radical polymer exhibiting ferromagnetic coupling.
由于有机自由基具有高反应活性，尤其是当它们发生铁磁耦合时，合成高自旋有机聚合物一直是一项艰巨的任务。在本文中，我们报告了获得高自旋有机聚合物的方法，其中使用了一种相对稳定的芴基自由基作为主要自由基单元，并且三嗪用作促进它们之间铁磁耦合的连接体。最初，通过氰基单体的环三聚反应合成了抗磁性聚合物前体。随后，使用O(6)或I(7)氧化相应的阴离子聚合物获得了高自旋聚合物。从超导量子干涉仪测量获得的温度相关磁矩和场相关磁化数据揭示了主要自由基单元之间的铁磁耦合，耦合常数分别为7.5 cm和38.6 cm。对于6和7，自由基形式的主要单元百分比分别为29%和47%。值得注意的是，这标志着首次报道的表现出铁磁耦合的高自旋芴基自由基聚合物实例。
