An efficient electrochemical oxidation of C(sp3)-H bond for the synthesis of arylketones

Abstract

An efficient electrochemical oxidation of C-H (sp3) bond was developed with carbon rod as the anode and platinum counter electrode as well as the routine tetrabutylammonium tetrafluoroborate as electrolyte in an undivided cell. Using water as both co-solvent and sole oxygen source, more than 20 examples of arylketones were facilely synthesized in good to excellent yields (up to 92%) in the air under the constant current of 6 mA without external oxidants, base or mediators. The possible electrochemical reaction mechanism was also proposed. And the key intermediate 2u of pharmaceutical dyclonine was highly efficiently prepared through applying this electrochemical method. This electrochemical driven oxidation reaction has the advantages of simple operation and mild reaction conditions, as will provide a sustainable approach for alkane oxidation to aldehyde or ketone. We envision that our method will be useful for applications in the future industrial production of fine organic chemicals.