Synthesis of Unsymmetrical 2,6-Diarylanilines by Palladium Catalyzed C-H Bond Functionalization Methodology

3,5-Dimethylpyrazole was employed as a mono-d entate directing group for palladium-catalyzed ortho-sp(2) C-H arylation with aryl iodides. The reaction shows good functional group tolerance and outstanding selectivity for mono-orthoarylation. Ozonolysis of ortho-arylated arylpyrazoles gave acylated biphenylamines that were further arylated to afford unsymmetrically substituted 2,6-diarylacetanilides.