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DOI: 10.1055/s-0035-1562518
A Straightforward Entry to γ-Trifluoromethylated Allenamides and Their Synthetic Applications
Publication History
Received: 28 April 2016
Accepted after revision: 23 June 2016
Publication Date:
01 August 2016 (online)
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Abstract
γ-Trifluoromethylated allenamides were obtained in good to excellent yields through a base-induced isomerization from the corresponding protected trifluoromethylated propargylic amines. This method, which simply required the treatment of the starting propargylic amines with sodium hydroxide in THF, was found to be fairly general and tolerates various alkyl and aryl substituents and a range of protecting groups on the nitrogen atom. The reactivity of the γ-trifluoromethylated allenamides was explored and they were found to be excellent substrates for radical- and gold(I)-catalyzed cyclizations yielding fluoro-alkylated nitrogen heterocycles.
Key words
allenamides - trifluoromethyl - copper-mediated reaction - isomerization - radical reaction - gold(I) catalysisSupporting Information
- Supporting information for this article is available online at http://dx.doi.org/10.1055/s-0035-1562518.
- Supporting Information
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References and Notes
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For a recent (and rare) use of allene as a ligand scaffold, see:
Reviews:
For related gold-catalyzed anellations, see: