Substituent effect on the electronic properties of pyrazino[2,3-g] quinoxaline molecules
作者:Teck Lip Tam、Feng Zhou、Hairong Li、Jane Chieh Yu Pang、Yeng Ming Lam、Subodh G. Mhaisalkar、Haibin Su、Andrew C. Grimsdale
DOI:10.1039/c1jm12347e
日期:——
We report the synthesis and characterization of pyrazino[2,3-g]quinoxaline derivatives with a systematic change in the substituents at the 2, 3, 7 and 8 positions and with or without 2-thienyl at the 5 and 10 positions to study the substituent effect and quinoid character of such a system. We performed density functional theory calculations using the B3LYP functional and 6-31G* basis set under the geometry optimization condition, together with the resonance effect of a valence bond theory to understand the electronic structures of these molecules. It was found that a combination of conjugation and cross-conjugation effects is responsible for the observed trends in their electronic properties, thus giving insights into designing molecules utilizing such effects.
我们报告了吡嗪并[2,3-g]喹喔啉衍生物的合成和表征,这些衍生物在 2、3、7 和 8 位上的取代基发生了系统性变化,在 5 和 10 位上有或没有 2-噻吩基,从而研究了这种体系的取代基效应和喹啉特性。我们在几何优化条件下使用 B3LYP 函数和 6-31G* 基集进行了密度泛函理论计算,并利用价键理论的共振效应来了解这些分子的电子结构。结果发现,共轭效应和交叉共轭效应的结合是导致观察到的电子特性趋势的原因,从而为利用这种效应设计分子提供了启示。