When Aryldiazonium Salts Meet Vinyl Diazoacetates: A Cobalt‑Catalyzed Regiospecific Synthesis of <i>N</i>‑Arylpyrazoles

A cobalt-catalyzed C–N bond formation between aryl diazonium salts and vinyl diazoacetates has been developed under relatively mild conditions. The <i>N</i>-arylpyrazoles have been prepared in moderate to high yields in a regiospecific way