Catalytic dehydrative amide bond formation using aqueous ammonia: synthesis of primary amides utilizing diboronic acid anhydride catalysis.

Although aqueous ammonia is an inexpensive and readily available safe source of ammonia, there have been no successful studies on direct catalytic dehydrative amidations of carboxylic acids with aqueous ammonia. In this study, we report a catalytic methodology for the synthesis of primary amides through diboronic acid anhydride (DBAA)-catalyzed dehydrative condensation of carboxylic acids with aqueous ammonia as the amine substrate.