The reaction of the readily available N-methyl-N-phenylcinnamamides with phenyliodinebis(trifluoroacetate) (PIFA) in the presence of Lewis acids provides a general and efficient assembly of a variety of 3-arylquinolin-2-one compounds. This novel approach features not only metal-free oxidative C(sp2)–C(sp2) bond formation but also an exclusive 1,2-aryl migration.