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Updated: Sep 4, 2025
Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Photocatalytic Reductive Olefin Hydrodifluoroalkylation Enabled by Tertiary Amine Reductants Compatible with Complex
Jonathan D Ellefsen1, Scott J Miller1
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States.
Abstract:
Noncanonical amino acids (NCAAs) are imperative to many facets of chemistry and biology. Herein, we report a method for the reductive hydrodifluoroalkylation of olefins that utilizes triethylamine base as the terminal reductant. The alkene acceptors include a range of electronically diverse alkenes, chief among them, dehydroalanine in variously protected forms, which provides access to synthetically relevant NCAA scaffolds under mild and general reaction conditions. We have demonstrated that a chiral auxiliary may be incorporated to provide diastereocontrol for pro-stereogenic substrates. Mechanistically motivated experiments provide some insight into the reaction mechanism, which supports a terminal step involving proton transfer for electron-poor olefins, while H atom transfer assisted by a thiol cocatalyst may complete the catalytic cycle for electron-rich olefins. The protocol is found to be compatible with additions to complex molecules, including the natural product thiostrepton.
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