Copper(I)/Copper(II)-Assisted Tandem Catalysis: The Case Study of Ullmann/Chan-Evans-Lam N1,N3-Diarylation of 3-Aminopyrazole

Article abstract of DOI:10.1002/cctc.201500510

Unprecedented Cu^I/Cu^II-assisted tandem catalysis allowing an Ullmann/Chan-Evans-Lam sequence was achieved. This three-component, one-pot reaction triggered by a change in the oxidation state of the metal leads to the selective N¹,N³-diarylation of 3-aminopyrazole. This new method should be a valuable tool for small-molecule drug discovery that requires suitable regio- and/or chemoselective strategies for the N-arylation of nitrogen-containing heterocycles. Tandem power: The first assisted tandem copper-catalyzed process, triggered by a change in the oxidation state of the metal, is developed to allow a one-pot Ullman/Chan-Evans-Lam sequence leading to the selective N¹,N³-diarylation of 3-aminopyrazole.