A bridged two-vial system aminocarbonylation protocol where Mo(CO)(6) functions as an external in situ solid source of CO has been developed. For the first time both nitro group containing aryl/heteroaryl iodides and bromides gave good to excellent yields in the Mo(CO)(6)-mediated and palladium(0)-catalyzed conversion to benzamides, while the identical one-vessel protocol afforded extensive reduction of the nitro functionality. The above-mentioned bridged two-compartment protocol furnished good results with both primary amines and secondary amines and sluggish aniline nucleophiles at 65-85 °C reaction temperatures.