| 研究実績の概要 |
The purpose of this project is the selective functionalization of C(sp3)-H bonds by exploiting a hybrid radical/organometallic reactivity of first row transition metals such as iron, manganese, cobalt, or nickel. Based on a previous discovery of the hybrid dual reactivity of organoiron, which behaves both as a radical to cleave a C(sp3)-H bond under mild conditions and as an organometal to create a new C-C or C-heteroatom bond, this research aims at the development of an efficient hybrid catalytic system for the selective functionalization of both simple, bulk hydrocarbons and of complex molecules such as steroids.
During FY2018, we found that an iron salt and deprotonated carbazole form an amidoiron complex that in the presence of an aryl iodide and upon visible light irradiation aminates the alfa position of THF, or the allylic position of an alkene. While these results are preliminary, they demonstrate that the hybrid reactivity of first row transition metals can be initiated by light, instead of the previously used reactive Grignard reagents.
We also discovered a new reactivity of organomolybdenum species, which activated an aryl chloride to promote a homocoupling or a cross-coupling reaction.
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| 現在までの達成度 (区分) |
現在までの達成度 (区分)
3: やや遅れている
理由
During FY2018, I moved from the University of Tokyo to the RIKEN Center for Sustainable Resource Science, and during April-August I build up the laboratory from scratch. We started experiments from the end of August 2018, and people started joining the team during October-December. Thus, during FY2018 we could do research for less than 6 months, and therefore the development of the project was slower than expected.
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| 今後の研究の推進方策 |
During FY2019, I plan to further investigate the light-promoted hybrid reactivity of first row transition metal species. Thus, not only iron, but cobalt, manganese, or nickel amides will be irradiated with visible light, and their reactivity towards an aliphatic bond in the presence on an aryl iodide will be investigated. The optimization studies will be performed for the amination of alkenes at the alllylic position; the ultimate goal of this project, the amination of simple alkanes will also be studied. For preliminary studies, the catalytic turnover was poor; the reasons for the poor stability of the catalyst will be studied in order to achieve efficient reactions at low catalyst loading.
The reactivity of organomolybdenum species towards aryl chlorides will be studied, especially applications to molybdenum-catalyzed cross-coupling of aryl chlorides and related reactions.
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