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Synlett 2019; 30(03): 356-360
DOI: 10.1055/s-0037-1611694
DOI: 10.1055/s-0037-1611694
letter
Lewis Acid-Catalyzed Rearrangement of Fluoroalkylated Propargylic Alcohols: An Alternative Approach to β-Fluoroalkyl-α,β-enones
This research project was funded by Ministry of Science and Technology, Taiwan (MOST 105-2113-M-039-004) and “Chinese Medicine Research Center, China Medical University” from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) in Taiwan (CMRC-CHM-6).Further Information
Publication History
Received: 07 November 2018
Accepted after revision: 02 December 2018
Publication Date:
03 January 2019 (online)
Abstract
A practical Lewis acid-catalyzed Meyer–Schuster rearrangement of fluoroalkylated propargylic alcohols, leading to a series of β-fluoroalkyl-α,β-enones, is developed. The methodology reported herein features moderate to high yields and high stereoselectivity in the synthesis of β-alkyl-β-fluoroalkyl-α,β-enones.
Key words
Lewis acids - Meyer–Schuster rearrangement - β-trifluoromethyl-α,β-enones - metal triflates - fluorinated compoundsSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1611694.
- Supporting Information
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References and Notes
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- 24 All of the synthetic β-fluoroalkyl-α,β-enones were characterized according to their 1H NMR, 13C NMR, 19F NMR, and mass spectra. The stereochemistry of (E)-β-alkyl-β-fluoroalkyl-α,β-enones was unequivocally determined by comparing their NMR spectra to those of structurally identical or similar compounds.
For Brønsted acid-promoted Meyer–Schuster reactions, see