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Synthesis of Imidazo[1,2-a]pyridines: Triflic Anhydride-Mediated Annulation of 2H-Azirines with 2-Chloropyridines

Frédéric Vuillermet, Joanick Bourret and Guillaume Pelletier*

*Department of Chemical Sciences, Paraza Pharma Inc., 2525 avenue Marie-Curie, Saint-Laurent, Québec H4S 2E1, Canada, Email:

F. Vuillermet, J. Bourret, G. Pelletier, J. Org. Chem., 2021, 86, 388-402.

DOI: 10.1021/acs.joc.0c02148

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The reaction between 2-chloropyridines and 2H-azirines provides imidazo[1,2-a]pyridines, an heterocyclic moiety commonly found in medicinal chemistry leads and drugs. Thorough optimization of the activation/cyclization resulted in good yields for a variety of substituted heterocycles.

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proposed reaction mechanisms

Key Words


ID: J42-Y2021