Pd-catalyzed ortho-arylation of phenylacetamides, benzamides, and anilides with simple arenes using sodium persulfate

We report a mild and efficient Pd-catalyzed ortho-arylation of phenylacetamides, benzamides, and anilides with a range of simple arenes using sodium persulfate (Na(2)S(2)O(8)). This green strategy generates biaryl C-C bonds from two unactivated sp(2) hybridized C-H bonds. Electron-rich and electron-neutral arenes underwent oxidative arylation under our optimized reaction conditions. In substrates bearing two reactive ortho C-H bonds, selective diarylation via quadruple C-H bond functionalization was possible. The same reaction conditions were extended to an intramolecular cross-coupling for preparing lactams. The synthesis of relevant trifluoroacetate-bridged bimetallic Pd complexes derived from anilides and their stoichiometric reactivity were investigated.