Miklík David, Fatemeh Mousavi S, Burešová Zuzana, Middleton Anna, Matsushita Yoshitaka, Labuta Jan, Ahsan Aisha, Buimaga-Iarinca Luiza, Karr Paul A, Bureš Filip, Richards Gary J, Švec Pavel, Mori Toshiyuki, Ariga Katsuhiko, Wakayama Yutaka, Morari Cristian, D'Souza Francis, Jung Thomas A, Hill Jonathan P
International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Ibaraki, Japan.
Institute of Organic Chemistry and Technology, Faculty of Chemical Technology, University of Pardubice, Pardubice, Czech Republic.
Commun Chem. 2021 Mar 10;4(1):29. doi: 10.1038/s42004-021-00470-w.
Acenes and azaacenes lie at the core of molecular materials' applications due to their important optical and electronic features. A critical aspect is provided by their heteroatom multiplicity, which can strongly affect their properties. Here we report pyrazinacenes containing the dihydro-decaazapentacene and dihydro-octaazatetracene chromophores and compare their properties/functions as a model case at an oxidizing metal substrate. We find a distinguished, oxidation-state-dependent conformational adaptation and self-assembly behaviour and discuss the analogies and differences of planar benzo-substituted decaazapentacene and octaazatetracene forms. Our broad experimental and theoretical study reveals that decaazapentacene is stable against oxidation but unstable against reduction, which is in contrast to pentacene, its C-H only analogue. Decaazapentacenes studied here combine a planar molecular backbone with conformationally flexible substituents. They provide a rich model case to understand the properties of a redox-switchable π-electronic system in solution and at interfaces. Pyrazinacenes represent an unusual class of redox-active chromophores.
由于其重要的光学和电子特性，并苯和氮杂并苯处于分子材料应用的核心位置。其杂原子多样性是一个关键因素，会强烈影响它们的性质。在此，我们报道了含有二氢 - 十氮杂并五苯和二氢 - 八氮杂并四苯发色团的吡嗪并并苯，并将它们作为氧化金属衬底上的一个模型案例来比较其性质/功能。我们发现了一种独特的、依赖于氧化态的构象适应性和自组装行为，并讨论了平面苯并取代的十氮杂并五苯和八氮杂并四苯形式的异同。我们广泛的实验和理论研究表明，十氮杂并五苯抗氧化但抗还原不稳定，这与其仅含碳氢的类似物并五苯相反。此处研究的十氮杂并五苯将平面分子主链与构象灵活的取代基相结合。它们为理解溶液中和界面处氧化还原可切换π电子系统的性质提供了一个丰富的模型案例。吡嗪并并苯代表了一类不同寻常的氧化还原活性发色团。
