Abstract The purple-coloured iron peroxo complex [Fe (III) EDTA (η 2-O 2)] 3− as a novel reagent system for Pd-catalyzed decarboxylative ortho-acylation of acetanilides with α- oxocarboxylic acids at room temperature in aqueous media has been realized. This reaction provides an effective access to ortho-acylacetanilides under mild conditions.