Heterogeneously Catalyzed Aerobic Oxidation of Methane to a Methyl Derivative

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-2 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.

Automated summary

An efficient strategy for direct methane conversion involves protecting methanol by esterification to a more stable methyl ester. A new approach using a dispersed cobalt catalyst shows improved reaction conditions and competitive yields compared to traditional homogeneous catalytic methods. This method also utilizes a specific solvent system for product separation and recovery, enhancing overall efficiency.