Watanabe Hiroyuki, Tanaka Kazuo, Chujo Yoshiki
Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Polymers (Basel). 2021 Nov 20;13(22):4021. doi: 10.3390/polym13224021.
We report the synthesis and absorption properties of homopolymers consisting of 1,3,4,6,9b-pentaazaphenalene (5AP). Oxidative polymerization in the Scholl reaction was accomplished, and various lengths of homopolymers can be isolated. It should be noted that we scarcely observed the generation of structural isomers at the connecting points, which is often observed in this type of reaction. Therefore, we were able to evaluate electronic structures of the synthesized homopolymers. In addition, it was observed that absorption bands were obtained in the longer wavelength region than the monomer. The computer calculation suggests that the highest occupied molecular orbital (HOMO) energy levels could be lowered by electronic interaction through spatially-separated HOMOs of 5AP. Moreover, we can evaluate the extension of the conjugated system through the meta-substituted skeleton and distance dependency of the main-chain conjugation.
我们报道了由1,3,4,6,9b-五氮杂菲（5AP）组成的均聚物的合成及吸收特性。在肖尔反应中完成了氧化聚合反应，并且可以分离出不同长度的均聚物。应当指出的是，我们几乎没有观察到在连接点处结构异构体的生成，而在这类反应中结构异构体的生成是经常会观察到的。因此，我们能够评估合成的均聚物的电子结构。此外，观察到吸收带出现在比单体更长的波长区域。计算机计算表明，通过5AP在空间上分离的最高占据分子轨道（HOMO）之间的电子相互作用，最高占据分子轨道（HOMO）能级可能会降低。此外，我们可以通过间位取代骨架和主链共轭的距离依赖性来评估共轭体系的延伸。
