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Updated: Jun 8, 2025

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Enabling Unfavorable Hydroamination Reactions Using a Chemoselective N-O Bond Reduction
Huy M Ly1, Hala Almeneim1, Monica A Gill1
1Centre for Catalysis Research and Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada.
Abstract:
Despite major advances, intramolecular alkene hydroamination reactions often face limitations. Herein, a redox-enabled process featuring oxidation of an amine to a hydroxylamine, a concerted hydroamination step, followed by catalytic reduction of N-oxide is shown to be broadly applicable. Catalyst screening and optimization showed that a K2OsO2(OH)4-pinacol complex rapidly and chemoselectively reduces the N-oxide cycloadduct in the presence of hydroxylamine and dimethyl sulfoxide. This selectivity was exploited to drive the equilibria toward complex products.
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