Development of an inexpensive fluoride ion sensor using complexes that can be used in field work

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05589
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 34030:Green sustainable chemistry and environmental chemistry-related
• Research Institution: Kyoto University (2022); Osaka Electro-Communication University (2020-2021)
• Principal Investigator: TOYAMA Mari 京都大学, 複合原子力科学研究所, 助教 (90373018)
• Co-Investigator(Kenkyū-buntansha): 茶山 健二 甲南大学, 理工学部, 教授 (10188493) ; 長尾 憲治 明治大学, 理工学部, 専任教授 (60245800)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ルテニウム(II)錯体 / フッ化物イオン / センサー / コバルト錯体 / 結晶構造解析 / 水素結合 / キュバン錯体 / NMRスペクトル

Outline of Final Research Achievements

Ruthenium(II) complexes with four reaction sites with F- were synthesized and their crystal structures, reactions with F- in solution, and structures of the reaction products with F- were investigated. The complexes reacted with F- at a maximum ratio of 1:3 and showed a clearly visible color.
In order to reduce the cost of raw materials, we synthesized the corresponding complexes with cobalt(III), which reacted visibly with F-, but it was difficult to improve the yield to more than 55%. Therefore, the target was changed to a cobalt(II) complex, which was easy to synthesize (80% yield) and reacted with F- to produce a product with very low solubility. Furthermore, the product was found to be a tetranuclear complex with a Co4-F4 cubane skeleton (85% yield).

Free Research Field

錯体化学

Academic Significance and Societal Importance of the Research Achievements

本研究では安価で簡単な手順でフッ化物イオン（F-）を検出できる試薬（錯体）の開発を試みた。まず、モル吸光係数の大きな（色が鮮やかな）ルテニウム(II)錯体で、F-の検出が人の目で溶液の色の変化としてわかる検出試薬を合成した。更に、より安価な検出試薬となるようコバルト錯体で2種類の研究を行なった。１つ目の錯体はCo(III)錯体で、変化はルテニウム(II)錯体ほど顕著ではないが、F-の検出が目視でわかる試薬を合成した。２つ目はCo(II)錯体で、検出試薬の溶液にF-を加えると、生成物が析出する（溶液が濁る）試薬を合成した。