Stereoselective synthesis of 2,5,6-trisubstituted piperidines
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Updated: Oct 1, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Abstract:
[reaction: see text] A short and efficient synthesis of 2,5,6-trisubstituted piperidines was achieved by a combination of an aza-Achmatowicz oxidation of a furyl benzenesulfonamide, conjugate addition to the resulting 2H-pyridinone, and subsequent addition of various nucleophiles to a transient N-sulfonyliminium ion. The steric bulk of the tosyl group directs attack of the nucleophile from its opposite side, thereby leading to the formation of cis-substituted products.
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