Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, 464-8603, Nagoya, Japan.
Spectroscopy Laboratory for Functional π-Electronic Systems and, Department of Chemistry, Yonsei University, 03722, Seoul, Korea.
Chemistry. 2023 Apr 21;29(23):e202300249. doi: 10.1002/chem.202300249. Epub 2023 Mar 15.
The relationship between the overall electronic structure of π-conjugated molecules and the arrangement of their constituent elements is of fundamental importance. Establishing rational design guidelines for conjugated hydrocarbons with narrow HOMO-LUMO gaps is useful to develop near-infrared (NIR) responsive dyes and redox-active materials. This study describes the synthesis and properties of three conjugated hydrocarbons, i. e., an indenonaphthoperylene, an indenoterrylene, and a diindenoterrylene. These molecules exhibit NIR absorption despite the absence of significant antiaromaticity and diradical character. Notably, the indenonaphthoperylene exhibits red-to-NIR emission in the 620-850 nm region. The indenoterrylene and the diindenoterrylene exhibit NIR absorption tailing to 870 and 940 nm, respectively. Moreover, the effect of the π-extension of indenoperylene is disclosed in order to propose guidelines for achieving a narrow HOMO-LUMO gap with negligible antiaromaticity and diradical character.
π 共轭分子的整体电子结构与其组成元素的排列方式有着至关重要的关系。为具有较窄 HOMO-LUMO 能隙的共轭烃建立合理的设计准则，对于开发近红外（NIR）响应染料和氧化还原活性材料是有用的。本研究描述了三种共轭烃的合成和性质，即茚并萘并[1,2-b]对二𫫇英、茚并[2,1-b]对二𫫇英和二茚并[2,1-b:1',2'-f]对二𫫇英。尽管这些分子没有明显的反芳香性和双自由基特征，但它们仍表现出近红外吸收。值得注意的是，茚并萘并[1,2-b]对二𫫇英在 620-850nm 区域显示出红到近红外的发射。茚并[2,1-b]对二𫫇英和二茚并[2,1-b:1',2'-f]对二𫫇英分别表现出近红外吸收拖尾至 870nm 和 940nm。此外，还揭示了茚并芴的 π 扩展效应，以提出实现具有可忽略的反芳香性和双自由基特征的窄 HOMO-LUMO 能隙的指导原则。
