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Heterogeneously Catalyzed Aerobic Oxidation of Methane to a Methyl Derivative.

ABSTRACT: A promising strategy to break through the selectivity-conversion limit of direct methane conversion to achieve high yields is the protection of methanol via esterification to a more stable methyl ester. We present an aerobic methane-to-methyl-ester approach that utilizes a highly dispersed, cobalt-containing solid catalyst, along with significantly more favorable reaction conditions compared to existing homogeneously-catalyzed approaches (e.g. diluted acid, O₂ oxidant, moderate temperature and pressure). The trifluoroacetic acid medium is diluted (<25 wt %) with an inert fluorous co-solvent that can be recovered after the separation of the methyl trifluoroacetate via liquid-liquid extraction at ambient conditions. Silica-supported cobalt catalysts are highly active in this system, with competitive yields and turnovers in comparison to known aerobic transition metal-based catalytic systems.

SUBMITTER: Blankenship AN

PROVIDER: S-EPMC8456920 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Heterogeneously Catalyzed Aerobic Oxidation of Methane to a Methyl Derivative.

Blankenship Andrea N AN Ravi Manoj M Newton Mark A MA van Bokhoven Jeroen A JA

Angewandte Chemie (International ed. in English) 20210705 33

A promising strategy to break through the selectivity-conversion limit of direct methane conversion to achieve high yields is the protection of methanol via esterification to a more stable methyl ester. We present an aerobic methane-to-methyl-ester approach that utilizes a highly dispersed, cobalt-containing solid catalyst, along with significantly more favorable reaction conditions compared to existing homogeneously-catalyzed approaches (e.g. diluted acid, O<sub>2</sub> oxidant, moderate temper ...[more]

PMID: 34076327

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