The phosphine-free palladium-based catalytic system Pd(OAC)2/DABCO has been developed for the carbonylative transformations of aryl halides with formic acid. The DABCO acts as a base as well as N-donor ligand to coordinate with metal ions and stabilize Pd-catalytic sites during the reaction process. Using DCC as the activator of formic acid and PEG as the reaction media. The aryl halides have been conveniently transformed into the corresponding aldehydes
in moderate to excellent yields.