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Updated: Jul 12, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Click chemistry reactions in medicinal chemistry: applications of the 1,3-dipolar cycloaddition between azides and
Gian Cesare Tron1, Tracey Pirali, Richard A Billington
1Dipartimento di Scienze Chimiche, Alimentari, Farmaceutiche e Farmacologiche and Drug and Food Biotechnology Center, Università degli Studi del Piemonte Orientale "A. Avogadro", Via Bovio 6, 28100 Novara, Italy. tron@pharm.unipmn.it
Abstract:
In recent years, there has been an ever-increasing need for rapid reactions that meet the three main criteria of an ideal synthesis: efficiency, versatility, and selectivity. Such reactions would allow medicinal chemistry to keep pace with the multitude of information derived from modern biological screening techniques. The present review describes one of these reactions, the 1,3-dipolar cycloaddition ("click-reaction") between azides and alkynes catalyzed by copper (I) salts. The simplicity of this reaction and the ease of purification of the resulting products have opened new opportunities in generating vast arrays of compounds with biological potential. The present review will outline the accomplishments of this strategy achieved so far and outline some of medicinal chemistry applications in which click-chemistry might be relevant in the future.
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