Manganese Dioxide–Methanesulfonic Acid Promoted Direct Dehydrogenative Alkylation of sp³C–H Bonds Adjacent to a Heteroatom

Abstract

A manganese dioxide (MnO2)-methanesulfonic acid (CH3SO3H) oxidation system has been developed to efficiently promote direct coupling of benzylic ethers and carbamates with simple ketones via oxidative C-H bond activation. The alkylation proceeds smoothly under air atmosphere to afford the corresponding products in good to excellent yields (53-87%). The employment of the combination of MnO2 and CH3SO3H is attractive on the basis of economical and environmental issues.

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“…In 2013 Lou et al. demonstrated the dehydrogenative coupling of benzyl ethers and carbamates with simple ketones through double C−H activation using the MnO 2 ‐methanesulfonic acid oxidation system . The reaction was found to be tolerant to atmospheric air and showed moderate to good yields with various functional groups.…”

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