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Updated: Jul 4, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Catalytic synthesis of saturated azacycles using transborylation
Nojus Cironis1, Nathan McRae1, Jack Stubbs1
1EaStCHEM School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ, UK. stephen.thomas@ed.ac.uk.
Abstract:
A simple, catalytic synthesis of pyrrolidines through the intermolecular cyclisation-homologation of azido-butenes was enabled by a hydroboration, 1,2-metallate rearrangement and B-N/B-H transborylation reaction sequence. Substitution at the C1-C3 positions of the azido-butenes was well tolerated. Extension of this methodology to azido-propenes and azido-pentenes with the aim of accessing azetidines and pyrrolidines respectively revealed the formation of an aza-bora heterocycle and a saturated azido-pentane boronic acid pinacol ester.
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