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DOE OSTI · 1974385

Selective Methane Oxidation by Heterogenized Iridium Catalysts

Li, Haoyi·Fei, Muchun·Troiano, Jennifer L.·Ma, Lu·Yan, Xingxu·Tieu, Peter·Yuan, Yucheng·Zhang, Yuhan·Liu, Tianying·Pan, Xiaoqing·Brudvig, Gary W.·Wang, Dunwei
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Abstract

Oxidative methane (CH 4 ) carbonylation promises a direct route to the synthesis of value-added oxygenates such as acetic acid (CH 3 COOH). Here, in this paper, we report a strategy to realize oxidative CH 4 carbonylation through immobilized Ir complexes on an oxide support. Our immobilization approach not only enables direct CH 4 activation but also allows for easy separation and reutilization of the catalyst. Furthermore, we show that a key step, methyl migration, that forms a C–C bond, is sensitive to the electrophilicity of carbonyl, which can be tuned by a gentle reduction to the Ir centers. While the as-prepared catalyst that mainly featured Ir(IV) preferred CH 3 COOH production, a reduced catalyst featuring predominantly Ir(III) led to a significant increase of CH 3 OH production at the expense of the reduced yield of CH 3 COOH.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYalkylscarbonylationcatalystsselectivitytransition metals

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Li, Haoyi, Fei, Muchun, Troiano, Jennifer L., Ma, Lu, Yan, Xingxu, Tieu, Peter, Yuan, Yucheng, Zhang, Yuhan, Liu, Tianying, Pan, Xiaoqing, Brudvig, Gary W., Wang, Dunwei. 2023-01-03. Selective Methane Oxidation by Heterogenized Iridium Catalysts. https://doi.org/10.1021/jacs.2c09434

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