Electrochemical Synthesis of Chiral Heterohelicenes

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K15281
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 33020:Synthetic organic chemistry-related
• Research Institution: Osaka University
• Principal Investigator: Sako Makoto 大阪大学, 大学院薬学研究科, 助教 (20804090)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ヘリセン / 電解合成 / デヒドロヘリセン / 連続反応 / 円偏光発光 / ヒドロキシカルバゾール

Outline of Final Research Achievements

Efficient syntheses of heterohelicenes were achieved by utilizing electrochemical synthesis using easily procurable starting materials. By subjecting hydroxycarbazole and 2-naphthol derivatives to electrochemical synthesis, we succeeded in efficiently providing hetero[7]helicenes having multiple heterocyclic rings in their frameworks and dehydro[7]helicenes, which are 8-membered ring products formed by oxidative ring closure between aromatic rings at both ends of a hetero[7]helicene. The chiral optical properties of the optically pure forms of both compounds were evaluated, and it was found that they possess circularly polarized luminescence properties.

Free Research Field

有機合成化学

Academic Significance and Societal Importance of the Research Achievements

既存のヘリセン型分子の合成は、多段階合成や遷移金属触媒を用いる手法がほとんどであり、高温条件や複雑な反応基質を必要としていた。それに対して本成果の電解合成は、単純な反応基質を用いた連続反応によりヘテロヘリセン類を効率よく供給でき、持続可能な環境調和型反応である。また、得られたヘテロヘリセンおよびデヒドロヘリセン類は円偏光発光特性を有することから、機能性分子としての応用が期待される。