Pd-catalyzed selective N(3)-ortho C–H arylation of 1,4-disubstituted 1,2,3-triazoles

Pd(OAc)2-catalyzed direct C–H arylation of an arene triazole template has been explored using the triazole ring as a directing group. The N(3)-ortho C–H bond on C(4) aryl of 1,4-disubstituted 1,2,3-triazoles can be selectively arylated, exclusively affording the expected structures. The diarylated products could be selectively formed when the triazole derivative beared a para substituent on C(4) aryl of the heterocycle, while the monoarylated target molecules resulted from substrates with an ortho or meta substituent.