pi-Electronic Ionics: Synthesis of Charged pi-Systems That Form Assembled Structures

2021 Fiscal Year Final Research Report

• Project/Area Number: 18H01968
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 33010:Structural organic chemistry and physical organic chemistry-related
• Research Institution: Ritsumeikan University
• Principal Investigator: Maeda Hiromitsu 立命館大学, 生命科学部, 教授 (80388115)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: π電子系 / イオンペア / 集合体 / 電子物性

Outline of Final Research Achievements

In this research project, we have attempted to synthesize new charged π-electronic systems for fabricating their assemblies and electronic materials and devices and investigating the relations between the properties and assembling modes. In this study, porphyrin Au(III) complexes and deprotonated forms of meso-hydroxyporphyrins were found to act as π-electronic cations and anions, respectively, which form ion pairs in combination with corresponding counterions, resulting in the ordered arrangement and electronic and photophysical properties. The fundamental intermolecular forces between the charged components in the ion-pairing assemblies were examined, driving us to propose iπ-iπ interactions for the stacking of charged π-electronic systems. In addition, other building units of ion pairing assemblies, such as pyrrole-based anion-responsive π-systems and related molecules, were synthesized for electronic properties.

Free Research Field

有機化学・超分子化学

Academic Significance and Societal Importance of the Research Achievements

新たな荷電π電子系を開発し、その間にはたらく相互作用を制御・規則配列による電子機能性の発現によって、既存システムにはない分子集合体の化学を確立する契機を得ることができた。とくに、拡張π電子系に電荷を付与することで会合・集合化、材料形成を実現した点、また疑似的な荷電π電子系を与えるイオン応答性π電子系の新たな特徴を引き出した点、さらに新たな骨格を有するπ電子系を開発し、分子認識・集合化・電子物性を明らかにした点は、学術的に、また新たな分子素材による将来の応用展開の可能性を提示した点からも、社会的意義にも高い価値を示すものである。