Palladium-Catalyzed Direct C(sp2)-H ortho-Arylation of Anilides Using 2-Aminophenylpyrazole as the Directing Group

Palladium-catalyzed ortho-arylation of anilides was achieved using 2-aminophenyl-1H-pyrazole (2-APP) as a new directing group. Using Pd(OAc)(2) as the catalyst and AgO as the promoter, mono- and diarylation of anilides were realized in up to 89% isolated yield. Further manipulation of the arylation product may be accomplished by a 2-step sequence involving an acidic hydrolysis of the methylated amide. More interestingly, in the presence of K2CO3, tandem C-C/C-N cyclization products were obtained for a couple of substrates.