Creation of organic redox systems exhibiting electrochemical switching for the development of unimolecular devices

利用单电子传递信息的氧化还原系统，研究了分子器件的创建。自由基离子状态的低稳定性阻碍了新型分子器件的设计。为了提高稳定性，我们采用了双电子转移产生的封闭壳层体系。我们利用过渡金属催化反应记录的2位或6位取代的唑烯衍生物，利用一步双电子转移的概念制备了几种反应性分子。通过在azulene环上引入辛基或己氧羰基，提高了化合物的溶解度。我们还制备了以乙基为间隔的唑烯衍生物。用循环伏安法研究了新型π共轭化合物的氧化还原行为。这些化合物表现出假设的多重电子转移，这取决于azulene环的数量。根据我们最近提出的花青素-花青素杂化的概念，我们预计这些新的azulene衍生物将根据氧化还原状态表现出多种颜色变化。除了氧化还原行为外，这些化合物还表现出液晶行为。我们还制备了6-azulenyl取代的对苯二胺，表现出两性氧化还原行为。此外，我们还开发了新的azulenes有机金属试剂，并揭示了1-azulenylmethyl阳离子的键长变化。

Creation of molecular devices has been examined utilizing the redox systems with one-electron transfer for the transmission of information. The low stability of the radical ionic state hampered the design of novel molecular devices. We applied the closed shell system produced by two-electron transfer for the improvement of the stability. We have prepared several responsive molecules by the concept of one-step two-electron transfer utilizing the azulene derivatives substituted by 2-or 6-positions, which were archived by the transition metal catalyzed reaction. The solubility of the compounds was improved by the introduction of octyl groups or hexyloxycarbonyl groups on the azulene rings. We have also prepared azulene derivatives with ethynyl spacers. The redox behavior of the novel π-conjugated compounds was examined by cyclic voltammetry. These compounds exhibited the presumed multiple electron transfer depending on the number of azulene rings. We anticipate that these new azulene derivatives should exhibit multiple color change depending on the redox state owing to the concept of cyanine-cyanine hybrid proposed by us recently. These compounds also exhibit liquid crystalline behavior in addition to the redox behavior. We also prepared p-phenylenediamines substituted by 6-azulenyl groups, which exhibited amphoteric redox behavior. Furthermore, we have developed novel organometallic reagents of azulenes and also revealed bond-length alternation on the 1-azulenylmethyl cations.