In Situ Generation of Copper Nanoparticles by Rongalite and Their Use as Catalyst for Click Chemistry in Water

摘要

A novel,efficient and green protocol for the copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction by using copper nanoparticles (CuNPs),generated in situ by a green reducing agent,rongalite,is reported.Terminal alkynes reacted with benzyl,aryl and alkyl azides in the presence of copper nanoparticles and β-cyclodextrin (β-CD) in water.The reactions exclusively generated the corresponding regiospecific 1,4-disubstituted 1,2,3-triazoles in good to excellent yields.Notably,in situ generation of copper nanoparticles does not require any additional stabilizing agents or special reaction conditions.β-cyclodextrin plays dual role as a stabilizing agent as well as phase transfer catalyst.This protocol is also applicable for gram scale reactions.