Visible-Light-Induced Synthesis of Esters via a Self-Propagating Radical Reaction.

J Org Chem

College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.

Published: January 2025

We herein disclose a visible-light-induced synthesis of aryl esters through the cross-dehydrogenative coupling of aldehydes with phenols using BrCCl, in which phenolate functions as both a substrate and a photosensitizer. This transition-metal- and photocatalyst-free visible-light-induced esterification is suitable for a wide range of substrates and gives moderate to excellent yields (up to 95%). Mechanistic studies provided evidence of a self-propagating radical reaction involving homolytic cleavage of the aldehydic C-H bond and the formation of acyl bromides. BrCCl serves as an oxidant and a hydrogen atom transfer (HAT) agent.

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http://dx.doi.org/10.1021/acs.joc.4c02662DOI Listing

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