We describe a new approach to acid chloride synthesis via the palladium-catalyzed carbonylation of aryl iodides. The combination of sterically encumbered phosphines ((PBu3)-Bu-t) and CO coordination has been found to facilitate the rapid carbonylation of aryl iodides into acid chlorides via reductive elimination from ((Bu3P)-Bu-t)(CO)Pd(COAr)Cl. The formation of acid chlorides can also be exploited to perform traditional aminocarbonylation reactions under exceptionally mild conditions (ambient temperature and pressure), and with a range of weakly nucleophilic substrates.