Efficient synthesis of primary amides using 2-mercaptopyridone-1-oxide-based uronium salts

S-(1-Oxido-2-pyridinyl)-1,1,3,3-tetramethylthiouronium tetrafluoroborate (TOTT) and hexafluorophosphate (HOTT) are cheap and convenient reagents for the rapid and high-yielding preparation of primary amides when reacted with carboxylic acids and ammonium chloride in the presence of diisopropylethylamine. The reaction is chemoselective and undesired ammonolysis of other sensitive functional groups is not observed.