Aromatic nitriles play an important role in the preparation of high-performance polymers. In order to guide the rational design of new molecules, it is necessary to carry out systematic theoretical research on molecular structures. This article takes a new type of aromatic nitriles, pyrazine-2,3-dicarbonitrile (PQ) and its control group 1,4-dicyanobenzene (PN) as examples to conduct systematic theoretical research on their chemical environments using DFT calculation with experimental verification. Results show that the electronic effect of pyrazine withdraws the electron form cyano to pyrazine, which makes the cyano carbon more exposed and prone to nucleophilic reaction. This electronic deffect also causes the π-electron delocalization from cyano nitrogen to pyrazine, and results in a lower polarity of the cyano and an anomalous law for the ¹³C NMR shift of cyano carbon. In addition, pyrazine changes the stacking mechanism of PQ to be dominated by electrostatic force rather than commonly observed dispersion force-dominant π-π stacking in PN. This research method provides important guidance for the design of new crosslinkable aromatic nitrile and help to deepen our understanding of their structure-property relationship.

芳香腈在高性能聚合物的制备中发挥着重要作用。为了指导新分子的合理设计，需要对分子结构进行系统的理论研究。本文以新型芳香腈类化合物吡嗪-2,3-二甲腈（PQ）及其对照组1,4-二氰基苯（PN）为例，利用DFT计算和实验验证对其化学环境进行系统的理论研究。结果表明，吡嗪的电子效应将氰基的电子撤回到吡嗪，使氰基碳更加暴露，更容易发生亲核反应。这种电子缺陷还导致 π 电子从氰基氮离域到吡嗪，并导致氰基的极性降低以及反常定律^{氰基碳的13} C NMR 位移。此外，吡嗪改变了PQ的堆积机制，使其由静电力主导，而不是PN中常见的色散力主导的π-π堆积。该研究方法为新型可交联芳香腈的设计提供了重要指导，有助于加深我们对其结构-性能关系的理解。