Homoconjugation is a phenomenon discussed for various π-systems where classical conjugation is broken by e.g. methylene units but still a stabilization by electronic communication exists. In this respect, triptycene with its rigid C₃ symmetric geometry is an ideal scaffold to study this phenomenon. Although several studies based on triptycene strengthen the hypothesis of homoconjugation, in all described cases the electronic communication through space relies on different π-blades. Here, two triptycenes are presented having the exact same π-extended chromophore, but differently annulated to the bicyclic core. Both compounds were investigated by spectroscopic as well as computational means and compared with the corresponding model compound, elucidating the influence of the attachment site to the triptycene core on potential homoconjugation.

均相共轭是针对各种π系统讨论的现象，其中经典的共轭被例如亚甲基单元破坏，但仍然存在通过电子通信的稳定化。在这方面，三萜烯及其刚性C ₃对称几何是研究此现象的理想支架。尽管基于三萜的多项研究加强了均轭共轭的假设，但在所有描述的情况下，通过空间的电子通信都依赖于不同的π叶片。在此，给出了两个三联体，它们具有完全相同的π扩展发色团，但环化成双环核的方式不同。通过光谱学和计算手段对这两种化合物进行了研究，并与相应的模型化合物进行了比较，阐明了三萜烯核心的附着位点对潜在的共轭作用的影响。