Creation of New Extended Pi-Electronic Systems Composed by Conjugated Polyynes

本项目的目的之一是合成纳米级的平面pi电子化合物，并研究其性质，以阐明由sp和sp^2杂化碳组成的未知碳同素异形体的新性质。此外，还研究了高活性的三维共轭多炔的生成和环化在溶液或气相中合成富勒烯的方法，以及其在生成高级富勒烯和杂富勒烯中的应用。在扩展类石墨pi-体系的合成方面，制备了外大环化合物，并研究了它们的聚集行为；对溶液进行了研究。结果表明，这些分子在非极性溶剂中由于pi-pi堆叠相互作用而结合形成二聚体。相反，它们在极性溶剂中形成具有纳米管状结构的高聚集体，主要是由于疏溶剂相互作用。另一方面，开发了六乙基苯核心衍生物的高效合成方法，并将其用于石墨炔基序分子前驱体的合成。此外，还研究了引入碳碳三键和生成高活性中间体及其作为过渡金属配合物的拦截的新方法。对于由多环多炔合成富勒烯，我们成功地在多环多炔前驱体的激光解吸质谱中检测到C_<60 b>离子。该方法成功地检测了重氮富勒烯C_<58>N_2和低富勒烯C_<36>。然而，试图通过热解和烤箱激光分解前驱体来制备宏观量的C_<60>是不成功的。针对多环芳烃的环化反应，研究了二苯乙烯的热环化反应生成多环芳烃化合物。

On of the purposes of this project is to synthesize planar pi-electronic compounds of nanoscale regime and to investigate their properties to elucidate novel properties of unknown carbon allotropes composed by sp and sp^2-hybridyzed carbons. In addition, synthesis of fullerenes in solution or in vapor phase by the generation and cyclizatipn of highly reactive, three-dimensional conjugate polyynes was investigated as well as its application to the generation of higher fullerenes and heterofullerenes.With regard to the synthesis of extended graphite-like pi-systems the external macrocyclic compounds were prepared and their aggregation behavior in; solution was investigated. As a result, it was revealed that these molecules associate in non-polar solvents to form dimers due to pi-pi stacking-interactions. In contrast, they formed higher aggregates having nanotube-like structure in polar solvent mainly due to solvophobic interactions. On the other hand, the efficient synthetic method for the core hexaethynylbenzene derivatives was developed which was adopted to the synthesis of precursors of graphyne motif molecules. In addition, new methods for the introduction of carbon-carbon triple bonds and generation of highly reactive intermediates and their interception as transition metal complexes were investigated.Regarding the synthesis of fullerenes from polycyclic polyynes, we succeeded in the detection of C_<60> ions in the laser-desorption mass spectrometry of polyyne precursors. This method was applied to the successful detection of diazafullerene C_<58>N_2 and lower fullerene C_<36>. However, attempts to prepare macroscopic amount of C_<60> by pyrolysis and oven-laser decomposition of the precursors were unsuccessful. In connection to the polyyne cyclization, thermal, cyclization of diaryIdienynes to form polycyclic aromatic compounds was investigated.