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Updated: May 6, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Strain-Release-Driven Ring Opening of 3-Alkylideneazetidines To Access β-Halomethyl Allylamines
Qin Peng1, Caiqing Lin1, Haoqing Li1
1School of Chemistry and Chemical Engineering, Guangxi Colleges and Universities Key Laboratory of Applied Chemistry Technology and Resource Development, Guangxi University, Nanning, 530004, China.
Abstract:
An efficient, strain-driven ring opening of 3-alkylideneazetidines has been developed, enabling the one-step construction of both carbon-halogen and carbon-nitrogen bonds to afford structurally diverse β-halomethyl allylamines. This transformation is initiated by arynes as electrophiles, forming an azetidinium intermediate that undergoes nucleophilic attack by a halide anion to proceed with the ring-opening reaction. The protocol features the advantages of inexpensive and environmentally benign potassium halides as halogen sources, transition-metal-free conditions, and high stereoselectivity (E/Z). The utility of the resulting β-halomethyl allylamines was demonstrated by their further transformation into valuable allylamines and potential anti-inflammatory activity in preliminary bioassays.
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