Systematic luminescence characterization of antiaromatic compounds aimed at the design of novel rare-earth-like luminescent dyes

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02688
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 32020:Functional solid state chemistry-related
• Research Institution: Osaka University
• Principal Investigator: YAMASHITA Ken-ichi 大阪大学, 理学研究科, 講師 (40468145)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 反芳香族化合物 / 反Kasha発光 / 近赤外発光 / 有機発光色素

Outline of Final Research Achievements

While metal complexes, especially rare-earth complexes, exhibit diverse luminescence properties, common organic compounds usually emit only from the lowest excited state S1 in the UV to visible regions according to the Kasha's rule. In this study, we focus on antiaromatic compounds with the aim of realizing diverse luminescence properties in organic compounds comparable to those of rare-earth complexes.
The luminescence properties of isophlorin derivatives with different antiaromaticity were systematically evaluated. All of the antiaromatic isophlorins showed anti-Kasha dual fluorescence properties in the visible and near-infrared regions. On the other hand, isophlorin lacking antiaromaticity did not exhibit fluorescence. These results indicate that the introduction of antiaromaticity is an effective strategy to achieve dual fluorescence properties in organic compounds.

Free Research Field

構造有機化学・錯体化学・光化学

Academic Significance and Societal Importance of the Research Achievements

一つの色素から複数の発光を示す多重発光特性は、有機分子においては、実現するための一般的な分子設計は、申請者の知る限り現時点でほとんど知られていなかった。本研究では、反芳香族性が有機分子で多重発光、近赤外発光を実現するための合理的な分子設計指針であること明らかにした。これらの成果は、反芳香族ポルフィリノイドから、有機物で他に比類のない希土類錯体のような特異的発光特性を実現できる可能性を示すことができたと考えている。