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Updated: May 6, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Catalytic methyl transfer from dimethylcarbonate to carboxylic acids
Yuan Ji1, Jessica Sweeney, Jillian Zoglio
1Department of Chemistry, Smith College , Northampton, Massachusetts 01063.
Abstract:
Although methylation reactions are commonplace, currently used reagents are hazardous, toxic, and/or unstable. Dimethylcarbonate has been put forth as an inexpensive, nontoxic, and "green" potential methylating reagent. Herein we report a general, base-catalyzed methyl transfer from dimethylcarbonate to carboxylic acids. High selectivity for esterification is observed even in the presence of unprotected phenols, and the mild reaction conditions enable conservation of stereochemistry at epimerizable stereocenters. Isotope-labeling studies suggest a mechanism proceeding by direct methyl transfer from dimethylcarbonate to the substrate.
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