Apalladium-catalyzed intermolecular arylcarbonylation of unactivated alkenes has been developed. Unsymmetrical diaryliodonium salts (DAISs) were used as arylation reagents,t he bulkya ryl group (Ar L )o fw hich was exclusively incorporated into the arylcarbonylated products,w hich contained the Ar L group and acarboxylic ester group at the a-and b-carbon position, respectively,o ft he original terminal CÀC double bond. The reaction features excellent chemo-and regioselectivity,high functional-group tolerance,and very mild reaction conditions. Scheme 1. Transition-metal-catalyzed arylation of alkenes with unsymmetrical DAISs.