Kotwica Kamil, Kostyuchenko Anastasia S, Data Przemyslaw, Marszalek Tomasz, Skorka Lukasz, Jaroch Tomasz, Kacka Sylwia, Zagorska Malgorzata, Nowakowski Robert, Monkman Andrew P, Fisyuk Alexander S, Pisula Wojciech, Pron Adam
Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00664, Warsaw, Poland.
Department of Organic Chemistry, Omsk F. M. Dostoevsky State University, Mira av. 55A, Omsk, Russian Federation.
Chemistry. 2016 Aug 8;22(33):11795-806. doi: 10.1002/chem.201600984. Epub 2016 Jul 12.
Star-shaped conjugated molecules, consisting of a benzene central unit symmetrically trisubstituted with either oxa- or thiadiazole bithiophene groups, were synthesized as promising molecules and building blocks for application in (opto)electronics and electrochromic devices. Their optical (Eg (opt)) as well as electrochemical (Eg (electro)) band gaps depended on the type of the side arm and the number of solubilizing alkyl substituents. Oxadiazole derivatives showed Eg (opt) slightly below 3 eV and by 0.2 eV larger than those determined for thiadiazole-based compounds. The presence of alkyl substituents in the arms additionally lowered the band gap. The obtained compounds were efficient electroluminophores in guest/host-type light-emitting diodes. They also showed a strong tendency to self-organize in monolayers deposited on graphite, as evidenced by scanning tunneling microscopy. The structural studies by X-ray scattering revealed the formation of supramolecular columnar stacks in which the molecules were organized. Differences in macroscopic alignment in the specimen indicated variations in the self-assembly mechanism between the molecules. The compounds as trifunctional monomers were electrochemically polymerized to yield the corresponding polymer network. As shown by UV/Vis-NIR spectroelectrochemical studies, these networks exhibited reversible electrochromic behavior both in the oxidation and in the reduction modes.
合成了由苯中心单元与氧杂或噻二唑联噻吩基团对称三取代组成的星形共轭分子，它们有望作为分子和构建块应用于（光）电子学和电致变色器件。它们的光学（Eg（opt））以及电化学（Eg（electro））带隙取决于侧臂的类型和增溶烷基取代基的数量。氧杂二唑衍生物的Eg（opt）略低于3 eV，比基于噻二唑的化合物所测定的值大0.2 eV。臂中烷基取代基的存在进一步降低了带隙。所得到的化合物在客体/主体型发光二极管中是高效的电致发光体。扫描隧道显微镜表明，它们在沉积于石墨上的单层中也表现出强烈的自组装倾向。X射线散射的结构研究揭示了分子在其中有序排列的超分子柱状堆积的形成。样品中宏观排列的差异表明分子间自组装机制存在变化。这些化合物作为三官能单体进行电化学聚合，得到相应的聚合物网络。紫外/可见-近红外光谱电化学研究表明，这些网络在氧化和还原模式下均表现出可逆的电致变色行为。
