Oxidative para-Triflation of Acetanilides

Direct triflation of acetanilide derivatives with silver triflate has been accomplished under mild iodine(III)-mediated oxidative conditions. The reaction shows excellent regioselectivity for the pare position and tolerates a range of ortho and meta substituents on the aromatic ring. This method is also compatible with the preparation of arylnonaflates in synthetically useful yields.