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Updated: May 8, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
[Asymmetric syntheses of azacycloalkanes by one-pot [1+2+n] cyclization]
1Graduate School of Pharmaceutical Sciences, Kyoto University, Japan. Sharada@chiba-u.jp
Abstract:
Enantio- and diastereoselective one-pot synthesis of three- to seven-membered cis-azaheterocycles was achieved using a triggered asymmetric conjugate addition reaction of lithium amide with an enoate, followed by C- and N-alkylation of the resulting lithium 3-aminoenolate with α, ω-dihaloalkane, which can be regarded as a [1+2+n] cyclization. The usefulness of the developed methodology was clearly demonstrated by the short-step asymmetric syntheses of azirinomycin ester, nemonapride, and kopsinine.
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