text: A free radical is formed from the carboxylic acid in an oxidative decarboxylation with silver salts and an oxidizing agent. The oxidizing agent (ammonium persulfate) oxidizes the Ag(+) to Ag(2+) under the acidic reaction conditions. This induces a hydrogen atom abstraction by the silver, followed by radical decarboxylation. The carbon-centered radical then reacts with the pyridinium aromatic compound. The ultimate product is formed by rearomatization. The acylated product is formed from the acyl radical.