Synthesis of imides via palladium-catalyzed three-component coupling of aryl halides, isocyanides and carboxylic acids

A palladium-catalyzed three-component synthesis of acyclic imides from feedstock aryl halides, carboxylic acids and isocyanides through the intermediacy of isoimides has been developed. The key to the success of this approach was controlled isocyanide slow addition and organic/aqueous biphasic conditions. This transition-metal-catalyzed approach features readily available starting materials, atom- and step-economy, good functional group compatibility and gram-scale synthetic capability. Utilization of this new method is illustrated in the late-stage functionalization of drugs Carprofen, Loxoprofen and Flurbiprofen. This strategy has also been successfully applied in the synthesis of cyclic imides including phthalimide, homophthalimide, and 2H-2-benzazepine-1,3-dione derivatives.