An improved, modular synthesis of rigid, geometrically well-defined, alkyne-substituted tetracene (1) and pentacene (2) dimers is reported. The synthesis is rooted in sequential Diels–Alder reactions of a norbornyl tetraene with triisopropylsilylacetylene-substituted (TIPS-acetylene) quinone dienophiles. The incorporation of solubilizing and stabilizing TIPS-acetylene groups early in the synthesis affords a mild and reliable route, providing access, for the first time, to norbornyl-bridged pentacene dimers. A preliminary exploration of the excited state behavior of these molecules is also described.

中文翻译：

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用于单峰裂变的刚性多并苯二聚体的模块合成

据报道，一种改进的，模块化的，刚性的，几何定义明确的，炔烃取代的并四苯（1）和并五苯（2）二聚体的合成。该合成源于降冰片基四烯与三异丙基甲硅烷基乙炔基取代的（TIPS-乙炔）醌二亲二烯物的顺序Diels-Alder反应。在合成早期就加入了可溶和稳定的TIPS-乙炔基团，提供了一种温和而可靠的途径，这是首次获得降冰片烯桥联的并五苯二聚体。还描述了这些分子的激发态行为的初步探索。