Rapid Synthesis of Primary Amides Using Ammonia Borane

We report the rapid synthesis of primary amides by directly using commercially available ammonia borane (NH3·BH3), sodium hexamethyldisilazide (NaHMDS), and esters. The success of this protocol relies on NH3·BH3 as the nitrogen source being considerably more convenient and NaHMDS being an excellent proton abstractor but not participating in the nucleophilic addition reaction. The reaction had a wide substrate scope containing bioactive molecules, and most of the substrates were efficiently amidated over 90% yields.