An improved iron-mediated synthesis of N-2-aryl substituted 1,2,3-triazoles

Treatment of various chalcones and sodium azide in the presence of catalytic amounts of commercially available iron oxide nanoparticles, followed by the addition of aryl halides afforded N-2-arylated 1,2,3-triazoles in very good yields. This tandem three-component reaction involves an oxidative 1,3-dipolar cycloaddition of the chalcone and azide and subsequent regioselective N-2-arylation. The nano-catalyst is easily recoverable and can be reused without any significant loss in catalytic activity.