The Sequential Sonogashira-Click Reaction: A Versatile Route to 4-Aryl-1,2,3-triazoles

Abstract

Aryl halides can be easily transformed in a one-pot procedure into 4-aryl-1,2,3-triazoles with palladium/copper-catalyzed Sonogashira­-click reaction sequence, using trimethylsilylacetylene as acetylene surrogate.

Key words

alkynes - azides - cycloadditions - copper - cross-coupling

References

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6

When TBAF was added before the azide, 9% diphenylbuta-diyne was formed as by-product in the reaction mixture. With the addition of azide before the TBAF, we were able to suppress the homocoupling of the in situ formed terminal acetylene in every tested solvent. In EtOH-CH₂Cl₂ solvent mixture the amount of the diphenylbutadiyne side product remained below 1%.