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Updated: Apr 29, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Flexible stereoselective functionalizations of ketones through umpolung with hypervalent iodine reagents
1School of Chemistry, Cardiff University, Park Place, Main Building, Cardiff CF10 3AT (UK) http://www.cf.ac.uk/chemy/wirth.
Abstract:
The functionalization of carbonyl compounds in the α-position has gathered much attention as a synthetic route because of the wide biological importance of such products. Through polarity reversal, or "umpolung", we show here that typical nucleophiles, such as oxygen, nitrogen, and even carbon nucleophiles, can be used for addition reactions after tethering them to enol ethers. Our findings allow novel retrosynthetic planning and rapid assembly of structures previously accessible only by multistep sequences.
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