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Updated: Jan 8, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Strain-Release-Driven 1,3-Halo-hydroxylamination of Bicyclo[1.1.0]butanes Enabled by Anomeric Amide Reagents
Xiujuan He1, Wei Li2, Ting Zhang1
1School of Chemistry and Chemical Engineering, State Key Laboratory Incubation Base for Green Processing of Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, P. R. China.
Abstract:
A catalyst-free, strain-release-driven 1,3-halo-hydroxylamination of bicyclo[1.1.0]butanes (BCBs) is reported. This strategy employs anomeric amide reagents (N-protected N-halo-O-activated hydroxylamines) as difunctionalization reagents, yielding highly regioselective 1,1,3-trisubstituted cyclobutanes bearing both a hydroxylamine moiety and a halogen in a one-step manner. Preliminary mechanistic studies suggest this transformation may be involved in a radical chain pathway, and it is proposed that BCBs substituted with electron-withdrawing groups, such as esters or amides, are key to overcoming the challenge of radical polarity mismatch. Moreover, the synthetic utilities of these products are illustrated in the conversion into pyrrole derivatives and serve as nitrene precursors for metal-catalyzed aziridination of olefins.
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