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Updated: May 18, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
An efficient synthesis of bridged heterocycles from an Ir(I) bis-amination/ring-closing metathesis sequence
Ryan A Brawn1, Cristiano R W Guimarães, Kim F McClure
1CVMED Chemistry, Pfizer Worldwide Research and Development, 445 Eastern Point Road, Groton, Connecticut 06340, USA. ryan.brawn@pfizer.com
Abstract:
The amination of bis-allylic imidates using an Iridium(I) catalyst leads to the efficient formation of 2,6-divinyl heterocycles. Careful screening of amines, solvents, and conditions has led to the discovery of a system that favors formation of the desired cis products with synthetically useful levels of diastereoselectivity, and these results are further explained by computer based transition state energy calculations. Exposure of the heterocycles to ring-closing metathesis catalysts leads to the desired bridged heterocyclic systems.
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