Synthesis of cyclopenta-fused aromatic hydrocarbon radicals

共轭体系交替含有苯和环戊二烯基团（环戊融合多芳烃，CP-PAHs），以其特殊的性质而闻名，例如，适合用于光电应用。含有奇数个五元环的CP-PAHs处于中性自由基状态。在本项目中，自由基CP-PAHs将通过邻羧基或邻甲酰基取代的低苯基进行邻偶联合成。所得到的中间体应通过氧化或还原方法转移到共轭CP-PAHs中。在环戊二烯上的大量芳基取代基可以防止自由基中心的副反应。较高的CP-PAHs应该从含有芴基团的低聚芳基开始构建。介绍了合成含有最多11个环的CP-PAHs的方法。目标化合物的芳香、电子、磁性和氧化还原活性将被研究（部分与其他小组合作）。实验分析方法将得到量子化学计算的支持。

Conjugated systems, which alternately contain benzene and cyclopentadiene moieties (cyclopenta-fused polyaromatic hydrocarbons, CP-PAHs), are known for their special properties, making them, e.g., suitable for utilization in optoelectronic applications. CP-PAHs containing an odd number of five-membered rings are in their neutral state radicals. In this project radicalic CP-PAHs shall be synthesized by ortho-coupling in ortho-carboxyl- or ortho-formyl-substituted oligophenyls. The resulting intermediates shall be transferred into the conjugated CP-PAHs by oxidative or reductive methods. Side reactions at the radical centers can be prevented by bulky aryl substituents at the cyclopentadienes. Higher CP-PAHs should favorably be constructed starting with oligoaryls containing fluorene moieties. Methods are described for the synthesis of CP-PAHs containing up to eleven rings. The target compounds shall be investigated (partly in cooperation with other groups) with respect to their aromatic, electronic, and magnetic properties and their redox activities. The experimental analytical methods will be supported by quantum chemical calculations.