Tandem Oxidative Reaction of 1,3-Diarylpropenes and 5-Aminopyrazoles

Abstract The reaction of 5-aminopyrazoles with 1,3-diarylpropenes mediated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, with subsequent intramolecular cyclization and dehydroaromatization in the presence of Cu(OTf)2/tert-butyl hydroperoxide, gave a series of pyrazolo[3,4-b]pyridines in moderate to excellent yields. The reaction has the advantages of high atom economy, a wide substrate scope, and a one-pot procedure.