Development of photocatalytic methane transformation reactions using metallophilic interaction of d8 metal complexes

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K15582
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 34010:Inorganic/coordination chemistry-related
• Research Institution: The University of Tokyo
• Principal Investigator: Murata Kei 東京大学, 生産技術研究所, 助教 (80755835)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 光触媒反応 / パラジウム錯体 / 金属－金属間相互作用

Outline of Final Research Achievements

In this study, visible light-driven organic molecular transformations were explored using multinuclear d8 metal complexes with metallophilic interactions as catalysts. Through the screening of reaction conditions, the photochemical chlorine-atom abstraction reaction of a half-lantern type dinuclear palladium(II) complex possessing benzo[h]quinoline ligands was established. Using this reaction as a key elementary step, the visible light-driven C(sp2)-H bond chlorination reaction of benzo[h]quinoline was successfully developed, and the detailed reaction mechanisms were clarified by various experimental and theoretical analyses. Furthermore, the present principle was applied to the C(sp3)-H bond chlorination of 2-methylquinoline with the addition of an appropriate photoredox catalyst.

Free Research Field

有機金属化学・光化学

Academic Significance and Societal Importance of the Research Achievements

本研究において開発した可視光駆動型C-H結合塩素化反応は、可視光エネルギーによって活性な金属ラジカル種を発生させ、これを触媒分子の酸化・塩素化過程に用いる点に特色がある。その結果として、安価で取扱い容易な塩化炭化水素を塩素源に利用することが可能となり、従来法に比べ穏和な条件下での触媒反応が実現した。本原理はC(sp3)-H結合の塩素化にも適用でき、多様な炭化水素基質の変換に利用できる可能性がある。これらの研究成果は、金属－金属間相互作用を含む化学種を光触媒反応へ展開するための触媒設計指針を提示する点から、重要な意義をもつと考えられる。