The Creation of New pi-Electron Systems with Novel Properties and Functionality

为了在pi-共轭分子的化学方面有新的见解和发展，我们计划和开发了以下研究。这可能是在相当小分子的已知pi体系上发现新化学并将结果发展成新类型化合物的一种可行的方法。在这方面，我们研究了在外亚甲基碳上有离开基团(S)的五氟烯碱金属还原反应，得到了非常有趣的结果。这些结果带来了富烯齐聚物新的丰富的化学成果。在PI体系中加入非常规杂原子元素，如金属原子，将极大地扩展PI体系化学的领域和可能性。我们成功地合成了具有光学活性的芳基硼烷和甾烷，并研究了它们的构象行为及其作为手性手性试剂的可能性。我们还成功地生成了基态三重态有机硼化合物。我们成功地合成了低聚噻吩基-PE-…更多的富烯和-七富烯，高达四聚体，表现出有趣的氧化还原特性。我们还开发了一种相当新的化学方法，即用芳香环延伸的三亚甲基甲烷。这些中等分子量的pi-体系(扩展的pi-体系)有望带来丰硕的化学成果，我们正在继续积极的研究。为了开发新的扩展pi系统组，重要的是要设计出具有良好适用性的新的综合方法。重点研究了芳香族化合物的多区域选择性锂化合作用，得到了有趣的结果，并将其应用于低聚富烯和扩展的三亚甲基甲烷的合成。扩展的pi-体系由于其广泛的共轭作用通常会吸收可见光，而且它们的自由基和离子物种可以在一定程度上稳定下来，因此从物理化学的角度来看它们也是很有意义的。我们合成的一些扩展的三亚甲基甲烷在近红外区吸收了1060 nm的强光。最近，我们还开发了一些从有机亚铁磁学角度感兴趣的多重态分子。基于这些发现，我们期待着本项目的进一步发展。较少

In order to make new insights and developments in the chemistry of pi-conjugated molecules, we planned and developed the following studies.1. It may be a plausible way to find out something new chemistry on known pi-systems of rather small molecules and to develop the results into new type of compounds. In this regard, we examined alkali metal reduction of pentafulvenes having leaving group (s) at the exomethylene carbon and obtained very interesting results. These results bore fruit of new rich chemistry of fulvene oligomers.2. pi-Systems incorporating elements other than usual hetero-atoms, such as metal atoms, would greatly expand the field and possibility of the chemistry of pi-systems. We successfully synthesized optically active aryl boranes and stananes and studied their conformational behaviors and possible use as chiral chirating agents. We have also succeeded in the generation of ground state triplet organoboranes.3. We have been successful in the syntheses of oligothienyl-pe … More ntafulvenes and -heptafulvenes up to tetramers which show interesting redox porperties. We have also developed the quite a new chemistry of trimethylenemethanes extended with aromatic rings. These pi-systems of medium molecular weight (extended pi-systems) would promise fruitful chemistry and we are continuing active investigations.4. To develope new groups of extended pi-systems, it is important to devise new synthetic ways of good applicability. We especially studied multiply regioselective lithiation of aromatic compounds to use them as building blocks, obtained interesting results, and applied them to the syntheses of oligofulvenes and extended trimethylenemethanes.5. Extended pi-systems usually absorb visible light due to their wide conjugation, and their radical and ionic species can be stabilized to some extent ; thus they are interesting from physicochemical point of view too. Some of the extended trimethylenemethanes we synthesized absorb strongly light of 1060 nm in the near-infrared region. Recently we have been also developing a number of multiplet molecules which are of interest from the view point of organoferrimagnetism.Based on these findings we expect further development of the present project. Less