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Updated: Sep 3, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Ring Contraction of Bicyclic Lactams: A Molecular Editing Aza-Favorski-Type Approach to
Viktoria A Ikonnikova1,2, Kirill D Kungurtsev1,3, Pavel N Solyev4
1Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences , 16/10 Miklukho-Maklaya Street, Moscow117997, Russia.
Abstract:
Development of skeletal editing methods offers new horizons for the acceleration of drug discovery. An original aza-Favorski-type approach is described for the ring contraction of benzazepine-2-ones, providing versatile tetrahydroquinoline-2-carboxylic acids. The sequence employing silylation and Pb(OAc)4-promoted oxidative ring contraction affords variously substituted N-protected derivatives in ≤67% yields. The approach can also be applied to higher homologues, although with a lower efficiency.
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