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Updated: Aug 29, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Mechanistic considerations for the consecutive cyclization of 2,3-dibromopropylamine hydrobromide giving a strained
Kazuhiko Hayashi1, Yoshifumi Ikee, Satoru Goto
1Faculty of Pharmaceutical Sciences, The University of Tokushima, Sho-machi, Tokushima 770-8585, Japan.
Abstract:
The effective formation of 1-azabicyclo[1.1.0]butane (2) by treatment of 2,3-dibromopropylamine hydrobromide (1) with n-BuLi could be understood considering a rational reaction pathway via both transition states 10 and 19 based on the intramolecular Br...Li(+) coordination. A similar cyclization pathway starting from N-benzyl-3-bromopropylamine hydrochloride (17) to afford N-benzylazetidine (18) could also be postulated on the basis of a transition state 20 involving the intramolecular Br...Li(+) coordination.
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