The reaction of acetophenones with iodine(III) tris(trifluoroacetate) yields 3′- and/or 2-iodo derivatives, depending upon the substituent on the aromatic ring and the reaction conditions. The reaction was examined by changing the molar ratio of acetophenone versus the reagent, reaction temperature, and solvent. In similar reactions flavanones and coumarins gave iodo derivatives in which iodine is incorporated