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Updated: Apr 27, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
4-Hydroxy-6-alkyl-2-pyrones as nucleophilic coupling partners in Mitsunobu reactions and oxa-Michael additions
Michael J Burns1, Thomas O Ronson1, Richard J K Taylor1
1Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K.
Abstract:
Two mild and efficient strategies have been developed for the O-functionalisation of 4-hydroxy-6-alkyl-2-pyrones, by using them as nucleophilic partners in oxa-Michael additions and the Mitsunobu reaction. The reactions proceed in moderate to excellent yields on a range of substrates containing useful functionality. The reactions serve as practical and valuable synthetic methods to construct complex 2-pyronyl ethers, which are found embedded in a number of natural products.
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