| 研究課題/領域番号 |
23K04743
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| 研究種目 |
基盤研究(C)
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| 配分区分 | 基金 |
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| 応募区分 | 一般 |
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| 審査区分 |
小区分33020:有機合成化学関連
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| 研究機関 | 沖縄科学技術大学院大学 |
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研究代表者 |
クスヌディノワ ジュリア 沖縄科学技術大学院大学, 錯体化学・触媒ユニット, 准教授 (90747544)
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| 研究期間 (年度) |
2023-04-01 – 2026-03-31
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| 研究課題ステータス |
交付 (2023年度)
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| 配分額 *注記 |
4,680千円 (直接経費: 3,600千円、間接経費: 1,080千円)
2025年度: 1,560千円 (直接経費: 1,200千円、間接経費: 360千円)
2024年度: 1,560千円 (直接経費: 1,200千円、間接経費: 360千円)
2023年度: 1,560千円 (直接経費: 1,200千円、間接経費: 360千円)
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| キーワード | photocatalysis / naphthyridine / trifluoromethylation / cross-coupling / perfluoroalkylation / fluoroalkylation / catalysis |
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| 研究開始時の研究の概要 |
The introduction of fluorine-containing groups is a successful strategy to modify metabolic and biological activity of pharmaceuticals applied in chemical industry. However, efficient synthetic methods to introduce fluorine into organic molecules often require the use of expensive and often toxic precious metal catalysts as additives precluding commercialization of such molecules in industry. This project aims to develop alternative catalysts containing inexpensive metals (Mn, Fe, Co, Ni, Cu, Zn) and simple nitrogen-based ligands, especially for application in photocatalysis by visible light.
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| 研究実績の概要 |
During this fiscal year, photocatalytic C-N and C-O coupling catalyzed by nickel naphthyridine complexes has been developed and published at ChemCatChem. These results were highlighted at Chemistry Views, a Wiley chemical news journal. In this study, we use inexpensive first-row transition metal, nickel, as a catalyst for C-O and C-N bond coupling, which can be achieved under visible light irradiation (blue LED lamp) or under purple LED irradiation. The nickel catalyst differs from those reported in the previous literature and it is supported by a simple dimethylnaphthyridine ligand proposed in our group. The advantage is that our catalyst does not require precious metal-based additives based on ruthenium or iridium and it presents an alternative to previously reported systems using previously overlooked ligand motif.
In addition, the manuscript describing the synthesis and reactivity of zinc and copper perfluoroalkyl complexes is currently under review at the European Journal of Inorganic Chemistry. In this study, we explore coordination of a dimethylnaphthyridine ligands with copper and zinc perfluoroalkyl complexes. Given that copper complexes are widely used in trifluoromethylation chemistry, their detailed study with different ligand framework is important for understanding their structure, coordination chemistry, and reactivity. Zinc complexes are included for reactivity comparison with redox-innocent metal. We disclose the application of copper perfluoroalkyl complexes for defluorination/C-O bond formation and in aerobic alkene oxidation.
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| 現在までの達成度 (区分) |
現在までの達成度 (区分)
2: おおむね順調に進展している
理由
During the first year, one article is already published and another publication is in submission. These two publications closely followed the original proposed and describe developments in (a) photocatalytic C-O and C-N cross-coupling reactions and (b) synthesis and reactivity of perfluoroalkyl complexes with first-row metals; both directions combined with a common idea to develop new photocatalytic reactions catalyzed solely by first-row transition metals supported by previously underutilized naphthyridine ligand framework.
The exploration of other transition metals such as iron and manganese naphthyridine complexes was not trivial due to their lability. However, currently several complexes are already structurally characterized. New nickel complex synthesized in our group showed good catalytic activity in trifluoromethylation and C-O, C-N cross-coupling; however, in the next step will target less commonly used and less toxic metals such as iron and manganese which will required additional optimization.
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| 今後の研究の推進方策 |
During 2024 fiscal year, the article on copper and zinc perfluoroalkyl complexes will be published (currently submitted and under review).
Next, we plan to continue synthesis and characterization of bis- and tris-(dimethylnaphthyridine) complexes of Fe(II), Ni(II), Mn(II), Mn(I), Co(II), and Co(III). Some of these complexes have already been isolated and structurally characterized. After full characterization, these complexes will be tested in C-O and C-N cross-coupling and in trifluoromethylation in the presence of light. Preliminary results show that tris(naphthyridine) nickel complex has a comparable catalytic activity to our previously reported trifluoromethyl nickel complexes, and its advantage is simplicity in preparation. Based on the work of MacMillan, cobalt(III) complexes represent an interesting platform for developing non-precious metal catalysts with wide reactivity profile. Currently we obtained cobalt(II) complexes which we will attempt to oxidize to cobalt(III) and screen in a range of photocatalyzed reactions as an alternative to previous metal-based photoredox catalysts typically based on ruthenium or iridium.
Along another direction, we will explore the possibility of using cheaper CF3-group sources in trifluoromethylation alternative to Umemoto reagents. A range of different approaches will be used for their activation.
When photocatalytic activity is identified, mechanistic studies will be performed to elucidate the mechanism including experimental and theoretical investigation.
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