Transmission between various parts of molecules determines their reactivity and is important from the perspective of molecular recognition. In a recent paper, the correlation between substituent electronic properties and those of the rest of molecules has been studied using long substituted polyphenylene hydrocarbons. The distance attained between interacting sites (between a substituent and an extreme carbon atom) was 119 Å. The present study was planned to investigate whether similar interactions can be found when the transmitting medium is not a polyphenylene unit, but a polyene one. Some questions had to be answered: How rapidly do interactions between a substituent at one end of a molecule and phenyl ring at the other end decline with the increasing distance between two sites? How would this interaction change upon the removal of some polyene units from inside the molecule and what contribution would the units have to the through-space interactions? What measure characterizes the electronic properties of a substituent attached to the end of a polyenic chain? It was found that the through-space interaction contributions increased as molecules lengthened, but even for the longest molecules, the through-bond mechanism was responsible for about one half of the overall transmission whereas the through-bond transmission dominated for shorter molecules.

中文翻译：

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电子取代基效应沿多烯链的传输：对通过键和通过空间贡献的评估

分子各部分之间的传递决定了它们的反应性，从分子识别的角度来看很重要。在最近的一篇论文中，使用长取代的聚亚苯基烃研究了取代基电子特性与其他分子的电子特性之间的相关性。相互作用位点之间（取代基和极端碳原子之间）的距离为 119 Å。本研究计划调查当传输介质不是聚亚苯基单元而是多烯单元时是否可以发现类似的相互作用。必须回答一些问题：随着两个位点之间距离的增加，分子一端的取代基与另一端的苯环之间的相互作用下降的速度有多快？当从分子内部去除一些多烯单元时，这种相互作用会如何变化，这些单元对空间相互作用有什么贡献？什么措施表征连接到多烯链末端的取代基的电子特性？发现随着分子的延长，通过空间相互作用的贡献增加，但即使对于最长的分子，通过键机制负责总传输的大约一半，而通过键传输主要用于较短的分子。