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. 2023 Feb 24;25(7):1218-1222.
doi: 10.1021/acs.orglett.3c00313. Epub 2023 Feb 13.

2-Fluoroenones via an Umpolung Morita-Baylis-Hillman Reaction of Enones

Subrata Maity  1 , Alex M Szpilman  1
Affiliations

2-Fluoroenones via an Umpolung Morita-Baylis-Hillman Reaction of Enones

Subrata Maity et al. Org Lett. .

Abstract

Several methods have been reported for the formation of 2-fluoroenones. However, all these methods involve laborious multiple-step sequences with resulting low overall yields. In this paper, we report the first formal enone-α-H to F substitution, leading to 2-fluoroenones in a single step from ubiquitous enones in 63-90% yield. The reaction is applicable to a wide range of aromatic and alkenyl enones and is carried out at room temperature using HF-pyridine complex as the fluoride source. Mechanistic investigations support that the reaction takes place through a rare umpolung Morita-Baylis-Hillman-type mechanism.

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Conflict of interest statement

The authors declare no competing financial interest.

Figures

Scheme 1
Scheme 1. Simplified Possible Mechanisms
Scheme 2
Scheme 2. Scope of Enones in the Umpolung MBH Fluorination Reaction
Scheme 3
Scheme 3. Selected Transformations
See this image and copyright information in PMC

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