para-Selective copper-catalyzed C(sp2)–H amidation/dimerization of anilides via a radical pathway†
Copper-catalyzed amidation/dimerization of anilides via regioselective C(sp2)–H functionalization is achieved. The para-selective amidation is accomplished on the anilide aromatic ring via a radical pathway leading to C–N bond formation in the presence of ammonium persulfate as a radical source/oxidant for the copper catalyst. The developed protocol tolerates a wide range of anilide substrates. The regioselectivity is confirmed by single-crystal X-ray studies.