Marshall Jonathan L, Uchida Kazuyuki, Frederickson Conerd K, Schütt Christian, Zeidell Andrew M, Goetz Katelyn P, Finn Tristan W, Jarolimek Karol, Zakharov Lev N, Risko Chad, Herges Rainer, Jurchescu Oana D, Haley Michael M
Department of Chemistry & Biochemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States.
Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Chem Sci. 2016;7(8):5547-5558. doi: 10.1039/C6SC00950F. Epub 2016 May 13.
Indeno[1,2-]fluorenes (IFs), while containing 4n π-electrons, are best described as two aromatic benzene rings fused to a weakly paratropic -indacene core. In this study, we find that replacement of the outer benzene rings of an IF with benzothiophenes allows the antiaromaticity of the central -indacene to strongly reassert itself. Herein we report a combined synthetic, computational, structural, and materials study of and indacenodibenzothiophenes (IDBTs). We have developed an efficient and scalable synthesis for preparation of a series of aryl- and ethynyl-substituted IDBTs. NICS-XY scans and ACID calculations reveal an increasingly antiaromatic core from [1,2-]IF to IDBT, with IDBT being nearly as antiaromatic as the parent indacene. As an initial evaluation, the intermolecular electronic couplings and electronic band structure of a diethynyl IDBT derivative reveal the potential for hole and / or electron transport. OFETs constructed using this molecule show the highest hole mobilities yet achieved for a fully conjugated IF derivative.
茚并[1,2 - ]芴（IFs）虽然含有4n个π电子，但最好将其描述为两个芳香苯环与一个弱顺磁的茚并四烯核心稠合而成。在本研究中，我们发现用苯并噻吩取代IF的外部苯环会使中心茚并四烯的反芳香性强烈地重新显现出来。在此，我们报告了茚并二苯并噻吩（IDBTs）的合成、计算、结构和材料的联合研究。我们已经开发出一种高效且可扩展的合成方法来制备一系列芳基和乙炔基取代的IDBTs。NICS - XY扫描和ACID计算表明，从[1,2 - ]IF到IDBT，反芳香核心越来越明显，IDBT的反芳香性几乎与母体茚并四烯一样。作为初步评估，二乙炔基IDBT衍生物的分子间电子耦合和电子能带结构显示出空穴和/或电子传输的潜力。使用该分子构建的有机场效应晶体管（OFETs）展现出了完全共轭IF衍生物迄今所实现的最高空穴迁移率。
